American Mineralogist, Volume 66, pages 1022_1033, IggI

Surinagite, taaffeite, and heryllian sapphirinefrom pegmatitesin granulite-faciesrocks of caJey Bay,Enderby Land, fntarctica

Eowano S. Gnew

Department of Earth and Space Sciences U niv ersity of Caldo rni a Los Angeles, Califurnia 90024

Abstrect

Surinamite, taaffeite,berylliaa sapphirine,niobian rutile, ,and wagneriteoccur in sillimanite-rich, medium-grainedsegregations in two pegmaiitesofprobable late Archean age which granulite-facies.rocks cut near Mclntyre llaia-1erzz,s,4go05,E) in casey Bay, Antarctica. Antarctic surinamite contains 30.9-32.1wt.za sior, 33.7-37.3wt.vo Alror,9.i- l3'4 wt.Eo Feo, 0.01-0.2wt.vo Mro, and 16.4-1g.4wt.vo Mgo,0.5-r wt.voBe, and 0.66+0.2 wt'VoH2O. Assuming water is absent,a constantBeO content of 3.5 wt.Vo,and possibleFe3* for Al substitution, surinamite analysesrecast to 32 oxygenscontain 22 cations. Antarctic taafeite ,xt.vo conrains68.5-69.3 A12o3,9.7w.vo Feo, 10.6-11.0wr.% Mgo, 4.7-5.2 wt.vo zno, and'0.5-l wt.% Be. cell parameterssre a :5.6g04 (2)A, c : +t.tC4-(zt1, ,"gg"r,;g that this taaffeite gR is the polyrype.sapphirine contains zo.i wt.cosio2, 5 l. l wt.voAiror ani Be, 9:-l Y.E" indicating substitutionof Be for Al: Be + Si : 2Al. Associaredgarnet contains 33 to 42 mole vopyrope and associatedcordierite, I wt.7aNarO. Stablemineral assemblages in the segregationsat the time the pegrnatitescrystallized are quartz-sillimanite-surinamite- biotite-orthopyroxene-garnet, quartz-surinamite-taafeite, sillimanite-garnet-biotite-su- rinamite-taaffeite-sapphirine, and siltim4nite-garnet-biotite-chrysoberyl_surinamite.Tem_ peraturesand pressures at the time of pegmalils emplacementare estimatedto have been 800-900"c and 7-8 kbar. The Archean beryllian pegmatitesare interpreted to be of mag- matic origin and may be related to charnockitic plutonic rocks such as the body exposed& Tange Promontory 70 km to the west.

Introduction (Kozhevnikov et al., 1975). From the Musgrave Surinamite, a rare Mg-Al-Fe silicate mineral re_ Rangesof central Australia, Hudson et at. (196i) de_ scribed a taaffeite nodule sheathed by and containing minor beryllian sapphirine (Wilson and Hudson, 1967);the nodule occursin a phlogopite re_ placementzone in metapyroxenite.Teale (19g0) re_ ports taaffeiteand hdgbomiteenclosed in spinel por_ phyroblasts in a phlogopite rock from the Flinders Ranges(South Australia). The type taaffeite is a cut gemstoneof unknown provenance(Anderson el a/.. r95t). I report here a new paragenesisfor surinamite and taaffeite. These unusual minerals are present in sil_ Taaffeite,an oxide of Be, Al, Mg, and Fe, occursin limanite-rich segregationsin two pegmatitescutting metasomatic rocks and in high-grade metamorphic granulite-faciesrocks; associated minerals are garnet, terrains. In China, taaffeite occurs with chrysoberyl beryllian sapphirine, chrysoberyl, wagnerite, and so_ and spinel in lepidolite veins and in reaction skarns dian cordierite. Prior to my finds, surinamite, taaf_ in linestone cut by these veins (Beus, 1966,p. 33) feite, chrysoberyl and wagnerite had not been re- and in eastern Siberia, in nica- metasomatite ported from Antarctica (Grew, 1980a).I also present 000.3-oux/8 | /09 I 0- I 022$02.00 to22 GREW: SITRINAMITE, TAAFFEITE, BERYLLIAN SAPPHIRINE new X-ray powder and microprobe analytical data The granutite-faciesrocks of the Napier complex on taaffeite, surinamite, and on some of the associ- are cut by two generations of pegmalilss. An early ated minerals. The results of this study suggest that generation includes pegmatites dated radiometrically is an essential constituent of the Antarctic at 2500 million years (m.y.) (Grew and Manton, surinamite; de Roever (personal communication, 1979),some of which are shown in Figure l. These 1980) independently found significant beryllium in pegmatites are found at many exposuresin the Na- surinamite from the type locality. pier complex, but are nowhere abundant (see also Sheratonet al.,1980). Pegmatitesof the early genera- Geology of the pegmatltes tion form crosscuttingplanar veins up to I m across, Casey Bay and neighboring parts of Enderby Land irregular masses,some of which are associatedwith (66"30'-67"45'5and 48-53oE,Fig. l) are underlain boudinage, or pods. The last are generally 0.5-2 m by a late Archean (2500 m.y.) granulite-facies ter- thick and extend up to 4 m; they lie at a higb angle to rain, the Napier zone or complex (Ravich and Kame- the compositonal layering. The early pegmatiteshave nev, 1975,p. 2; Grew and Manton,1979; Sheratonet a granulite-facies mineralogy. Accessoryminerals in- aL, 1980).The Napier complex consistslargely of or- clude orthopyroxene, garnet, biotite, apatite' per- thopyroxene-quartz-feldspar gneisses ("charnock- rierite, zircon, sillimanite, ilmenite, rutile, monazite, itic" and "enderbitic" gneisses),pyroxene granulite, and locally cordierite, hornblende, and the rare min- garnetiferous gneisses, and subordinate aluminous erals to be described in more detail below' In a few and siliceous rocks, which are locally intruded by cases,the early pegmatites have an aureole of dark- anorthositicand charnockitic rocks (Fig. l). ened country rock a few cm thick. An example of

+ 6605 50"E Locolitiesfor BerylliumMinerols (Indicoted by Be) In EnderbyLond, Antorctico

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Fig. l. Map of a portion of thc Napicr complcx in Enderby Land showing localitics for surinamite, taaficitc, and beryllian sapphirinc ncar trlclntyre IstanOin Casey lay (indicated by Bc), Archean pegmatitcs of possiblc plutonic origin (small circles) are planar veins and podiform bodies, one of which was dated by Grew and Manton (1979). Sourccs of data: intrusive charnockitic rocks (7) on Tange Promontory (Ravich and Kamcncv, 1975,p. 494 Sheraton el al., 1980),east end of CaseyBay (J. W' Sheraton, p€rsonal communication, l9E0), and north of the Tula Mouatains (Ravich and Kamcnev, l9?5, p. 4%). Spccifc localitics of Soviet samplcs provided by Ye. N. Kamenev (personal communication, l9?8) and of Shcraton et aL's (19E0)two anorthosites by J. W. Shcraton (pffsoml communication" l9E0). GREW: SURINAMITE, TAAFFEITE, BERYLLIAN SAPPHIRINE such an aureole was sampled along a sillimanite- rocks within a tectoniczone of extensivedeformation bearing pegmatitenear Mt. Pyhagoras (Fig. l). The and retrogression.Pegmatites of the later generation country rocks here are osumilite granulites.The au- are abundant. reole is darker in color than the country rock and ap- The surinamite-bearing pegmatite consists of pearsto be richer in biotite. In placesno increasein coarse-grained(>l cm) quartz, microrcline,apatite, biotite was noted in the aureole;the darker color is biotite and sillimanite, and of medium-grained due to darkening of orthopyroxeneas contact with (mostly 0.05-2 mm) dense segregationsrich in sil- the pegmatiteis approached.Near the contact,ortho- limanite, garnet, cordierite, biotite, apatite, and su- pyroxene is partly replaced by garnet or a garnet- rinamite. In hand specimen, much of the microcline quartz intergrowth. The mineralogical changessug- is red. Sillimanite crystals(up to l0 cm long and 3 cm gest an increasein Fe/Mg ratio as well as in water across)are white or brown; brown sillimanite is chat- content of the host rock; temperatureswere suffi- oyant. The medium-grainedsegregations form irreg- ciently high for osumilite to remain in some layers ular veins,masses, and stringersup to 5 cm across.In within the aureole. addition to the above listed minerals, some samples The later generationincludes pegmatites dated ra- of the medium-grained segregationscontain ortho- diometrically at 520m.y. (Grew and Manton, lg79\. pyroxene, wagnerite, pynte, ilmeno-hematite, mag- The later pegmatitesare abundant in CaseyBay but netite, or monazite(Table l). In generalthe minerals are rare elsewherein Enderby Land. They form (l) exceptsillimanite lack preferredorientation. Sillima- cross-cuttingveins up to 4 m in width and up to at nite forms a few coarse prisms 0.5 to several cm in least 350 m in extent, (2) subconcordantpods, or (3) length and bundlesof prisms (mostly 0.05 to 0.2 mm large massesseveral meters and more across.Retro- acrossand up to 0.5 cm in length); someof the bun- gressionof the country rock by the pegmatitesoc- dles appear as fans in thin section. Pleochroic haloes curred under amphibolite-faciesconditions in au- are conspicuousin biotite, which is pale green to reoles generally no more than a few meters thick. brown, and in cordierite.Microveinlets (0.02-0.2 mm Accessoryminerals include biotite, muscovite,horn- thick) of biotite or cordierite cut garnet, sillimanite, blende, sphene, magnetite, allanite, beryl, kyanite, and, rarely, surinamite. Cordierite typically forms sillimanite, garnet, staurolite,, dumortier- aggregatesengulfing surinamite, garnet, biotite and ite, and, locally, sodian cordierite. Columbite-tan- finer-grainedsilliminals. In places,surinamite-quartz talite is present at Mount H6llingsworth (Fig. l), grain contacts are preserved. Orthopyroxene grains which is the first reported locatty for this mineral (0.07-0.4 mm across),a minor constituent, locally group in Antarctica (Grew, 1980a). have contacts with sillimanite and surinamite, or are The later generation of pegmatitesappears to be spatially and temporally related to tectonic zones of Table l. Mincralogy of the pegnatitic aggregates mylonitization and retrogression under amphibolite- Locality facies conditions. These zones are more extensively Sanple No. Section No. developed in the €astern part of Casey Bay than in Quartz -x other parts of the Napier complex. s i IliMni te (x) (x) x SurinaEi te (x) (x) x sapphirine (x) Description of the beryllim pegmatites Taa f feite (x) xx chrysobe!yl (x) x Surinamite and other rare minerals were found in Garnet x (x) x Oathopy!oxene two podiform pegmatites of the early generation (in- Cordierite Biotite dicatedby Be on Figure l), one at "Christmas Point" x xx Apatite x (informal name), at the south end of an unnamed is- Wagnerite Rutile x -x land 5 km WSW of Mclntyre Island (67"22'5, Magneti te -x 49o05'E),and the second at"Zirenn Point" (infonnal Mona zite = - = (Xl = name), a coastal exposure2 km soutl of Mclntyre Is- X present; abaentt probe analysiE 'Py!ite, ilrenohenatite, and K-feltlspar are present ln other land. sanples of this pegmatite. 2Incluales The "Christmas Point" pegmatite is 1.5 m thick several specirens which are contrDsitionally sihila!. rAs inclusion in garnet only. and is one of a seriesof en echelonpods in a layer of qPlagioclase, kyanj-te, and apatite present in quartz enclos- quartz granulite containing sapphirine, ortho- ing the aggregate. ssurinamite and taaffeite in quartz in smll offshoot of main pyroxene, sillimadls, and garnet. This granulite is aggregate. No quartz present in the Min aggregate. part ofa block ofrelatively unalteredgranulite-facies K-feLtlspar algo pregent in quartz encloging the aggregate. GREW: STJRINAMITE, TAAFFEITE, BERYLLIAN SAPPHIRINE separatedfrom them by only a selvageof cordierite 1977-1978and 1979-1980field seasons(Grew, 1978, (quartz also present).Wagnerite, (Mg,Fe)'POoF,oc- 1980a).Two samples from the "Christmas Point" curs in a yellow-brown aggregateI crn acrossand as pegmatite (22928,C) and three samples from the scatteredgrains to I mm ecrossin oee eection; grrbs "Zircnn Point" pegmatite (2234L(2,3,4))were se- are in contact with quartz. lected for electron microprobe analyses(Table l) "Zircon Point" is composedof a well-layered se- from a total of l0 samplesthat I collectedfrom each quenceof gneissesand granulitesshowing much less pegmatite. evidenceof the retrogrademetamorphism con- The chemical compositions(except for BeO and spicuousat "Christmas Point." A few pegmatitesof HrO) are basedon electronmicroprobe analyses of I both generationsare present.The beryllian pegma- to 4 grains per section (automatedARL-EMX micro- tite, which has an indistinct contact aureole,consists probe). Minerals were analyzed in carbon-coated largely of quartz and yellow microcline. The quartz polished thin sectionsand the data were reducedby is cut by veinlets,stringers, and small masses(up to 6 the Bence-Albeemethod. The microprobe data on 3 cm across) rich in sillimanite. These segregations minerals (hand picked separates)were supplemented contain taaffeite,sapphirine, surinamite, garnet, bio- by semi-quantitativeemission spectrographic analy- tite (in separategrains and in microveinlets),chry- sesprovided by Richard V. Gaines.Water was deter- soberyl, apatite, rutile, and rare monazite (Table l). mined in surinamite (2292C)at the U.S. Geological Nfost segregationshave a margin of biotite and gar- Survey (courtesyof J. R. O'Neill) by weighing hy- net. Sillimanite, sapphirine,taaffeite, and surinamite drogen yield from a hand'picked 20 mg sample. commonly have a marked preferred orientation; this X-ray diffraction patternswere obtained with Mn- foliation lies at a high angle to the contacts of the filtered iron radiation in a I14.6 cm diameterDebye- segregations.Sillimanite forms bundles of prisms Scherrercamera. mostly 0.05 to 0.4 mm acrossand up to severalmm Duptcates of surinamite,sapphirine, and taaffeite long. Taaffeite forms plates 0.2 to about 2 cm in di- have been donated to the Smithsonian Institution. ameter; some thicker plates appear to consist of la- National Museum of Natural History Catalog num- minae differing in orientation. Sapphirine and su- bers are as follows: Surinamite 2292C-147434,sap- rinamite form irregular, tabular grains. Those of phirine 2282G-147435, and taaffeite 2234L-147436' sapphirine appear to be nearly 3 cm in diameter; those of surinamite, mostly 0.05 to 0.8 mm. Chry- Descriptionand chemistryof the minerals soberyl forms anhedral grains a few tenths to a few mm acrossembedded in sillimanite or, in one case,in Surinamile taaffeite. Microveinlets of biotite (mostly 0.02-0.2 mm thick) commonly cut garnetand,locally, also sil- The Antarctic surinamite in hand specimen is a limanite, sapphirine,and taaffeite. dark green-blue mineral resembling sapphirine. It Quartz is absentfrom the sillimanite-rich segrega- forms tabular plates (flattened parallel to (010) ac- tions. In section2234L(5) (Table l), surinamite, taaf- cording to de Roever et al., 1976) and appears to feite, and biotite are in contact with quartz; these have (010); cleavage at a high angle to (010) minerals are in a microveinlet that appearsto be an is not conspicuousin most grains (cf. de Roever et offshoot of a sillimanite-rich segregation.Surinamite al., 1976).The optical propertiesof the Antarctic su- is in direct contact with quartz. Taaffeite is mantled rinamite are similar to thoseof the type material de- by , but was probably in contact with quartz scribedby de Roeveret al. The optic plane is parallel prior to alteration. to (010).Pleochroism is spectacular:Z-gteentsh blue, In section 2234L(4\,kyanite, in prisms to 0.9 mm Y-purple, and X-pale yellow green. Dispersion of long, and plagioclaseare presentin quartz near the the optic axesis marked. sillimanite-rich segregation.The kyanite appearsto In sample 2234L(3), surinamite tablets have a be secondary. fixed orientation relative to a large, irregular sapphi- rine grain; the (010) planes of the two minerals are Field and analyticalmethods parallel and extinction is simultaneous.However, X The two mineral occurrencesand geologicalobser- and Z in surinamite are not parallel to the corre- vations reportedin this paper are basedon field work spondingaxes in sapphirine.The pleochroiccolors of which I undertook as a member of the Australian sapphirine in this sample appear to be less pro- National Antarctic ResearchExpeditions during the nounced versionsof the surinamite colors: Z-green' 1026 GREW: SURINAMITE, TAAFFEITE. BERYLLIAN SAPPHIRINE ish blue, I-blue, with a hint of purple, and X-very Table 3. Chemical composition of surinamite pale yellow-brown. Powder X-ray patterns Strensavs diffraction of "Christmas Localtty "Zlrcon Point" "christmesPolnt" Surinanl Ranlez- Point" (2292C) Sanple No. 2234L 2234L 22928 22C2C and of a "Zircon Point" (2234L(4)) sectlon No. (3) (4) ( 1) surinamiteare identical, exceptthat a few high-angle halysls No. -r2- reflections are less sharp in the pattern for 2292C wetsht Per Cen! (Table s1o2 32.06 3r -97 31.60 30,89 31.37 33.1 33.25 2). All but two of the lines reporred by de Tio2 0.03 0.04 0.02 0,05 0 Roever et al. (1976)which are accessibleto Fe radia- otzo3 37.30 36 58 35.20 33.8A 31.70 14.9 14.67 tion are presentin the films of the Antarctic samples. ctzo3 0.01 0.01 0 0.0r 0.02 0 - A large Feo3 9 t0 9.55 r0.38 13.40 12.64 L2.25 10.64 number of weak reflectionsare also present MnO 0.02 0.01 0.16 0.18 0.20 r.05 0 in the Antarctic patterns. Many of these reflections M8o r7 59 17.13 18.40 16.37 16.57 16.45 18.50 may also belong to surinamite and could have been zno 0.19 0.13 - 0. 12 - 0.05 obscuredin the filn of de Roeveret al. (1976)by flu- Beo! 3,5 3.5 orescenoeofiron excited by Cu radiation. Caos 0.18 0.24 0.09 0.lr 0.05 0,05 0 Na^o5 00 0 0 001 0 0 The chemical composition of the Antarctic surina- x-os 0.05 0 03 0.03 0.03 0.01 0 0 mite determined by electron microprobe analyses is 100.01 99.25 99.37 98.53 98.09 101.35 100.56

lons NorDlized to 22 Table powder 2. X-ray diffraction data for surinamite s1 5 956 5-999 5.904 5.903 6.003 5.t52 Tt 0 004 0.006 0.003 0,007 0 22g2cr 22i4Ll su!inah'? 2292C 2234L Surinm A1 8.167 8.tI3 7.751 7.632 7.600 7 1 Intensityl d q C Intensity ddd 615 554 Cr. 0.001 0.001 0 0.001 0.003 0 - AA AAA 0.400 0.500 0,500 - 0.100 Total 8.168 8.114 8.151 8.133 8,103 7-545 1.654

2.635 2.635 2 -64 2 x Lr54 I 2.515 2-51A r.135

2.364 2-364 2.37 10l 1.0443 I O43t cases,more ALO, (Table 3). Surinamite in sample 2 324 2-333 lc2 L 0442 2 -3r2 2.309 2- 315 Ar 1.0374 I .0360 2292C contains 0.66*0.2 ,xl.VoH2O (J. R. O'Neill, 2 -264 2 -26I 2 -27 lc2 1.0378 1.0360 2 .I99 2.199 2 -ta5 Ar 1.o325 1.03rt personal communication, 1980;the large error is at-

2.064 2 063 2-O4 2cr L0208 I 02OO tributed to the small amount of sample analyzed, 20 I.997 1.99a r -99 lc2 I 02lo 1.0201 1.9a8 1.985 1.96 2cr I 0128 1.0115 mg). 1.915 1.914 r -92 lo2 l.oI23 l.ol14 1.841 1.839

l.aI7 t.816 1.816 lcl t.0OI3 0_99971 purity of a few peroent biotite, for the most intense _'--_r n^r 1.789 L?aa 2d2 l.OOI2 O.9999' biotite lines appear in the X-ray powder pattern 1.76Id l - 750d r -762 3Ct 0.9956 O.9944r ^ ^^. r.72Id t.7l9d r 122 2d2 O.sgSA O.SSSO' "'"" 1.596d 1.594d 1.596 2ct 0.9891 0 9880 (Table 2); this biotite could contribute 0.I to 0.2 *.Vo

I-544 I 543

*Biotite equivalent to about 1.5to 3 wt.VoBeO.No other ele- or sillimnit€ tupurity. d - diffuse reflection, x = r€ftection present, but cdnot be reasurd- present rOtainea ment analyzed spectroscopicallyis in signifi- with Un-fittered Fe radiation. Camra dimler 114.6 m. Film @rlected for shri*age cant amounts.The small amount of zinc reported in 2Pron de bever et al. (1976, asfe z). microprobe may not 3vi$al the analyses be significant; less estinate- than O.OlVowas detectedspectroscopically. GREW: SUNNAMITE, TAAFFEITE, BERYLLIAN SAPPHIRINE lo27

Tablc 4. Emission sp€ctrographic analyses of sapphirine, The high Fe3* contentsof the "Christmas Point" surinamite and taaffeite (F. Savino, Analyst). ln weigbt percent of surinamite are consistent with compositions of asso- the element(major elementsnot includcd). ciated minerals: sillimanite at "Christmas Point" 0.9 to l.l wl.VoFerOt but that at "Zitcon Sapphirine Taaffeite Surindite contains 2234L(3't 22A2c 2234L 2292C Point," oriy 0.4Vo.ffus highsr Mg/Fe2* and lower

BA <0.01 <0.01 <0.01 <0.01 Mn/Fe2* ratios of the "Zirc'on Point" surinamite rel- EE 0.5-1.0 <0.0r 0.5-r .o 0 -5-r.0 2292C from "Christmas Point" are B 0.01-o.05 <0.01 <0.01 <0.0r ative to sample 0.r-0.5 <0.0r 0.05-0. r 0.01-0.5 consistentwith the differencesin Mg/Fe and Mn/Fe Co 0.0r-0.05 <0.01 0 .0t-0 .05 <0.01 ratios in associatedgarnet (Table 5). However, su- Cu

<0.01 <0.01-0.05 <0.01 0 .01-0- 05 "Zireon Point" garnets. 0.01-0.05 0.0r-0.05 0.01-0.05 0.01-0.0s Zn <0.01 <0- 0r >10 Taafeite Li ---- Notdetected Taaffeite in hand specimenforms dark-green platy masses(flattened parallel to (001)) having a superfi- de Roever(personal communication, 1980) reports cial resemblanceto chloritoid (seealso Hudson et a/, that a few wl.Vo BeO (qualitative ion microprobe 1967).In thin section,taaffeite is very pale green and analysis)is present and that significant amounts of resemblescorundum. H* and OH- are not presentin surinamite from the The X-ray diffraction pattern of the Antarctic taaf- type locality. feite is similar to that for the 9R rhombohedral poly- In the absenceof a detailedcrystal structuredeter- type of Hudson et al. (1967) from the Musgrave mination of surinamite (crystal fragmentshave been Ranges in Australia and reflections can be indexed sent to P. B. Moore for study), a discussionof its chemistry can at best be tentative. For the purposes Tablc 5. Analysesofgarnet of the presentdiscussion, I assumethat water is not an essential constituent of surinamite, and that the Locality "Zircon Point" "christms Point" sample No. 2234L 2234L 22928 2292C deficiency in the microprobe analysesis made up by Section No. 24 I 3.5 wt. %BeO. This amount brings the analytical to- weight Per Cent tals of the Antarctic samplesinto the 9$-lffiVo nnge sio2 39.70 39.43 39.62 38.98 and results in a reasonablestoichiometry (Table 3). Tio2 0-0 0.02 However, the analytical total of the de Roever et a/. AI2O3 22.75 23.18 22.49 zz.>3 (1976)surinamite exceedsl0l7o. Cr2O3 0 0.01 0 0,02 I 28.01 27.82 30.28 Cations total near 22 for analysesof the "Zircon Feo 26.2L MnO 0.r8 0.14 1.55 1.05 Point" and type surinamites recast to 32 oxygens,the cell anion content proposed by Moore (1976). For M9o 11 1l tn q? 9.94 9.02 convenience, cation totals have been normalized to 1.18 L.27 0.68 0.44 22, and the number of oxygens for 22 cations com- ZnO 0,01 0 0.02 0.02 pared (Table 3). Na^O Kzo 0.04 0.03 0.0s 0.04 The number of oxygens for 22 cations in the "Zir- LOz.37 con Point" and type surinamitesis close to 32, but TotaI 101.37 r02.70 102.15 that for the "Christmas Point," and to a lesserextent, cations per 12 oxygen si 2.98L 2.948 2.988 2.962 the StrangwaysRange surinamites is less than 32. Ti 0 - 0 0.001 Ferric iron substituting for aluminum may explain A1 2.013 2.042 1.999 2.017 Cr 0 0.001 0 0.001 this difference. Reasonable oxygen totals are ob- Fe 1.646 1.751 1,755 1.924

tained if one assumesthat Al * Fe3* is constant at Mn o.oll 0.009 0.099 0.068 one value in the Antarctic samples and at another Mg L.265 L.172 1.rl8 1.021 Ca 0.095 0.102 0.055 0.036 value in the other two samples(Table 3). The differ-

encesbetween the two setsof samplesmay be related Total 8.012 8.031 8.013 8.029 to the substitution(Mg + Fe2*+ Mn) + Si: 2(Al + 'AII Fe'*). Fe as FeO. r028 GREW: SURINAMITE, TAAFFEITE, BERYLLIAN SAPPHIRINE

on the basisof their pattern (Table 6). The calculated Q6mpositionally, the Antarctic taaffeite is richer in unit cell parametemof the Antarctic taaffeite area: iron and poorer in Mg than other analyznd taaffeite 5.6E04(2)Aand c - 4t.lO4(Z)A, which are larger and is unique in its signifisancetenor of zinc (Table than those of the Musgrave Ranges taaffeite. This 7). Signifisantamounts of Be and Ga are also present site difference may be due to the substitution of Zn (Table 4). However,it is unlikely the gallium content and Fe for Mg (seebelow). exceedsl%o, for large amounts were not noted in an

Table 6' X-ray powder data for taaffeitc from Cascy Bay, Endcrby Land, Antarctica (Sample 2234L). Fe radiation. Mn frltcr.

Il 2 3 d(obs) hk12 d (calc) d (obs) d (obs) hkt2 d (calc) 2 d(obs)3

5 13.70 0.0.3 13.70 13.7 7 r.4L97 2.2.0 1.420r I .4189 I 5.846 0.0.5 6 .851 r.3669 0.2.2s r.3669 1.3682 - r.0.I 4.885 4.99 z.z.t 1. 3561 I . 3559 3 4.565 0.0.9 4.567 4.)t L.t.27 1.3418 L. 5442 3 4.222 0.1.5 4.22L 4.2L J t.3296 2.0.26 L.3299 r.3289 I 3.760!+ I.0.7 t.ttL 1.3188 J.I.d r . 3187 3 3.551 0.1.8 3.553 3.55 1.2800 1,0. 31 r.2802 t.2788 <1 3.432 0.0.12 3.425 3 L.2527 1. 3.13 L.2527 r.2539 3 3.148't I .0. l0 J. I)C 3.15 2 L.2378 3. 1.14 1 tala r.2360 3 2.970r, 0. 1. 11 2,976 2.975 1.1. 30 r.2340 r.2322

6 2.835* 1.1.0 2.840 2.836 4.0.1 1 L.2292 "O? 2 2.78L r.1.3 2.78L 2.776 I L.2216 4.0.4 1,.22tL L.2202 5 2,556* 1.0.13 2.550 2,658 1 I.2t65 0.4.5 L.ZlOJ t.2L54 I 2.623 1.1.6 2.624 2 r.2042 I.2.26 L.2044 L.2039 5 2.5L9 0. r. 14 2.52L 2.520 r. r676 0.4. 11 L.1682 1.1670 2.443 2.0.2 2.442 2.438 2 r.1419 0.0.35 1.1418 I. I4I4 10 2,4LO 1.1.9 2.4L2 2.408 I 1.1343* 0.4.L4 1.1344 1. 1330 I 2.388 0.2.4 2.392 2.390 <1 1.1180* 2.3.5 1.1181- 5 2.355 2,0.5 2.356 z, i)J <1 1.1097* 4.0. 16 1.1093 6 2.269 0.2.7 2.269 2.271 I I .1019 1 1 1' I .1019

2 2.108* 0.2.10 2. r11 2.108 1.0961 0.4.17 L.0962 6 2.0535 2.0.1r 2.0545 2.052 2et 1.0797] 2.L.3L I .0796 I .0790 L 1.9383* 0.2.l3 L.94L4 ]. 9390 Lcz r.0799' 3 1.8843 2.0.L4 I . 8855 1.8843 lcl | .0736 1.4.0 1.0735 L.072L I 1.8560* 2.L.L r.6) /) lat 1.0628 3.2.t3 1.0629 r .0525 - L.2.2 1 .8518 r.8548 2at r.0597I 1.1.35 1.0594 1 .0587 r.7756 0.2.15 L.77 66 L.7758 Lcz I .0591', - 1.2.8 | .7 484 r.7470 1cl 1.05341 2,3.r4 1.0534 3 1.7464 I.0.22 L,7 466 Laz 1.0533', 3 r.7239 2.O.t7 t.tzzg)

4cr 1.0450] I t.4.9 r, 6788 0. 1. 23 r.6797 h2 1.0450' I .0450 1 .0440 I r .6534 I . 2.11 r.6647 3cr 1.03841 2 2.2.7 1.6390 0.3.0 I .6398 1 .6380 2u2 1.0384' I .0384 I .0378 2 L.5236 0.2.L9 I.6244 L.6230 .lct 1.0332 3.2.16 r.0333 5 1.6020 2.L.L3 1.6028 I .6011 4ot L.0273.1 4.O.22 3 1.5697:t I.2.t4 1.5708 1.5690 3oz 1,0273' L.0273 L.0265 <1 1.5571 1.0.25 ]. 5594 3c1 1 0131] o.4.23 1.0131 5 L.5424t 0.3.9 1.5433 I .54t7 2ez 1.0132' <1 1.5218 0.0.27 1.5224 1. 5230 o.2.37 t.ot24 1.0120 2 1.5056 0.L.26 r,5051 1.5044 lat 0. 9930 L.2.35 0.9929 5 1.4875 0.2.22 r.4878 I.4868 4ct 0. 9848] c.v.z) 0.9848 I.2.t7 L.47 39 L.4742 3tz 0.9849' 0.9842 4 L.4453 2.0.23 L.4458 | ,4447 2el o.9707 0.4.26 0.9707 *Not lncluded ln cell reflnement. rVlsual egtLmates.' 2Based on hexagonal (rhonbohedral) cell of = 5.6804(2) i, c = af.f0a(2) i,. rlludaon e !! a1. (1957) {lludson g'1qal, (1957) lndexed thl6 reflection as 0.2.17. FiIn corrected for shrlnkage. Canera dlaneter - 114.6 ro. GREW: SURINAMITE, TAAFFEITE, BERYLLIAN SAPPHIRINE ro29

Tablc 7. Composition of taaffcite from "Zircon Point" Gage Ridge Qocated l0 km northwest of Mount $rthagoras, Fig. l) containing garnet' sillimanite, Sample No. 2234L 2234L minor sapphirine, spinel, and corundum, is com- Section No. 3 and parable (Table 8). Spectrographic analysesshow that weight Per cent ihe sapphirine n 2234L(3) contains 0.5 to l%oBe sio 2 0 0.05 TiO2 0 (Table 4). and low microprobe AI2O3 58.45 69.3r The anomalous composition Cr2O3 0.01 0.0r analytical totals can be explained as a result of beryl- - Feo r 9.69 9.10 lium substitution of Al such that Be * Si 2Al' MnO 0.0r 0.01 Reasonable stoichiometries and analytical totals are Mgo 10.64 r0.99 ZnO f.ro 4.55 Tablc 8. Composition of sapphirine Beo2 0. 11 CaO 0.09 Gage "Christmas Kzo 0.04 0.05 Lcality "zitcon Point"' RJ.dge Point" Sample No. 2234L 2234L 2045A 3 Total 99 -62 r00 . 35 section No. (3) (2)

sio2 20,26 19.15 16 .94 1 ? 15 Cationa per 8 oxygen - o.0r o.06 si 0 0.002 Tio2 AI 3.983 3.99r dzog 51.14 50.71 54.43 61 .34 0 0 0.0 o.o2 0 FE 0.400 0. 396 cr203 o.o2 Feo2 I0.05 9.90 LZ. J' 9.52 Mn 0 0 0.783 0.800 MnO o.o1 0.03 o.20 o.03 Z1 0.189 0.158 Be o.652 0.645 MgO 15.48 15.45 13.s2 L6.49 0.17 o .03 Total 6.008 6.002 ZnO Nio 0.09 0 rAII Fe as Feo 2Assumed content of Beo, from Hudson et aI. (1967) Beo3 2.5 2.2 1.0 o 3GaIIium content not included. Cao o.l5 0.o5 0.10 0 .10 Na2O 00 o *zo o.o3 0.o4 0.o5 0 .01 with the energy dispersive system on element scan BaO 0.0r the electron microprobe. Analyses recast to 8 oxygens 99.74 9?.55 99.25 100-87 assuming the BeO content of the Musgrave Ranges Total. taaffeite (5.5 ,nl.Vo)and neglecting Ga'O' result in cations for 20 oxygens reasonableanalytical totals and stoichiometry (Table qi 2.404 2.327 2.06'? l-592 ?). Significant amounts of FerO, are not required, for Ti - o.ool 0.006 there are nearly 4 Al per 8 oxygens.Taafieite oompo- A1 7.154 7.262 7.827 A-620 from one part of the pegmatite to an- sition varies o.oo2 0 0.002 0 other (Table 7), and some grains appear to be com- Fe3+2 0.037 o.Osl 0.026 0.196 positionally zoned. F"2+' 0.960 0.925 L.234 0.753

Sapphirine wl o.ool 0.003 0.o20 0.oo3 2.799 2.514 2.93L Sapphirine is a major constituent of sample M9 2.739 o.oo9 - 0.015 0.003 2234L(3) and occurs as a single inclusion in garnet in Zn o .009 sample 2234L(2) from "Zircon Point" (Table l). Ni. Be o.713 0.642 0.293 0 Compositionally, sapphirine of this locality is anom- alous; it contains more SiO, and less AlrO, (Table 8) Total 14.018 14.04r 14.ol3 14 .098 than any of the sapphirines in the compilations of lsapphirine in 2234L(3) is a mjor comPonent of the Deer et al. (1978,Table 64) 6d [liggins et al. (1979), rockr in 2234L(21 it is found only as a sml] of sapphirines from Enderby Laod (Ellis et al., inclusion in garnet. ?r 2+ and 2all re as Feo. In recast analyses. Fe-' and Fe-' 1980;Grew, 1980b)of which sample2282G is repre- are calculated fron stoichioretry (Higgins et a1', Enderby Land sapphirine, 1979) . sentative. Only one other 3estisted from stoichioretry (excePt 22a2G) . sample 2O45A, a quartzofeldspathic gneiss from GREIA: S URI NAM ITE, TAAFFEITE, BERYLLIAN SAPPHI RI N E

obtained by assuming BeO contents of 2.2 to 2.5 Table 9. Analyses of cordierite from ..Christmas point', wt.Vofor the "Zircon point" sapphirines and l%o for SanpIe the Gage Ridge sapphirine (Table g). By contrasr, 22928 22828 the sapphirine in sample 2282G, a qaartz granulite sio2 47.77 47.62 'Christmas from Point," contains insignificant Be TiO2 0.0t (Table 4) and its chemistry is similar to other En_ A1203 30.91 29.92 derbVLand sapphirines.Wilson and Hudson's(1967) Cr2O3 0 0.01 beryllian sapphirine (0.65 I wt.VoBeO) difiers from the Feo 3.55 6.62 Antarctic sapphirines in that there is no evidence of MnO 0.05 0.76 increasedsilica content; they report 14.42\ft.qo SlO2 u9o ll. 23 8.79 or 1.709Si per 20 oxygens. ZrLO 0. 13 An X-ray diflraction pattern of the ..Zircon point" BeO2 0.75 1.3 sapphirine (2234L(3)) is very simitar to, though not ..normal" CaO 0.11 0.20 identical with, one taken of a ,"pphirio., Na2O 0.98 1.68 sample 2M4H (see Grew, 1980b,Table 4). If there K20 0.06 0.05 are any crystallographic differences between these Total /t3 sapphirines, single crystal techniques will be needed 95. 97.08 to resolvethem. Cations per 18 Oxygen Co rdierit e and sillimanit Si 4.974 4.963 e Ti 0.001 A1 Cordierite associated with surinamite ,.Christ- 3.793 3.675 at Cr 0 0. 001

FE 0. 310 o.577 lln 0.005 0.057 M9 L.744 1.366 Zn 0.010 BE 0.188 0. 32s N on2282E) ca 0.012 0.022 suggestftaf signifigantamounts of BeO Na 0.197 0.339 K 0.008 0.007 Total LL.232 11.362 Fe as -BeO:AlI FeO content estimated fron Na2O content using cordierite analyses of eernf ind povondra (1966) and Schreyer et al. (fSZS). FerO, contents in sillimanite are 0.4 wt.Vofor sam_ ples2234L, 0.9Vo rn 22928, and l.lVo rn 2292C.CrrO, contents are negtgible. ciency in the analnical totals, then this rutile con- Other minerals tains about 90 mole VoTiO2 and l0 mole Voof Fe2*- Nb oxide having Fe:Nb ratios of roughly l:2 to.3:4, Chrysoberyl (identification confirmed by X_ray somewhat higher than other niobian rutiles (palache diffraction in one sample) is pale yellow in hand et al.,1944,p. 558). sample and mostly colorless in thin section. It con- Optical identifcation of wagnerite,(Mg,Fe).pOoF, tains 1.5 wt.VoFeO and less than 0.lVo CrrO, and was confirmed by the near identity of its X-ray pow- Tior. der pattern with that of Colorado wagnerite (Sheri- Rutile is found ,,Zirconpoint" only at and some is dan et al.,1976, Fig. l7A), in particular, the presence of reflectionsnear 5.65A and S.S2A. Parageneses The main stablesilicate mineral assemblagein the medium-grained segregationsat "Christmas Point" Elements scanswith energy dispersive detector re- at the time the pegmatites crystailized appears to veal the presenceof significant niobium and minor have been quartz-sillimanite-garnet-surinamite- tungsten, the latter probably not exceeding I wt.Voin biotite + orthopyroxene. In the segregationsat .Zir- amount. If NbrO, is assumedto make up the defi_ con Point,n'assemblages include sillimsnils-garnet- GREW: SURINAMITE, TAAFFEITE, BERYLLIAN SAPPHIRINE l03l sapphirine-surinamite-taaffeite+ rutile-biotite and sillimanite. [n addition, orthopyroxeneis not found sillimanite-garnet-chrysoberyl-biotite-surinamiteor in the later pegmatitesor in the amphibolite-facies (see 1979). taaffeite.Quartz was absentin the "Zircon Point" as- rocks of the tectoniczones also Kamenev, semblagesexcept in sample 2234L(5), in which a Consequently,the restriction of the surinamite and quartz-surinamite-taaffeite assemblageis present. taaffeite paragenesesto Casey Bay where the later Biotite appears to have been part of the "Zircon pegmatitesare most abundant is interpreted not to Point" assemblages,cordierite was absent.The dif- indicate a causal relation between these beryllium ferencesin the assemblagesfrom the two localities minerals and the younger pegmatites. may be due to compositionalfactors, e.g.,Fe/Mgra' The unusual assemblagesof beryllium minerals in tio, as indicated by garnet compositions,and Fe3* thesepegmatites may be due not only to high tem- contents, as implied by sillimanite FerO' contents peraturesof crystallizationrelative to thosefor other and Fe-Ti oxide assemblages.Compositional varia- beryllian pegmatites,but also to the relatively high tions within the pegmatite at each locality are re- MglFe ratio in the bulk corrposition of the Antarctic flected in variable compositionsof the minerals as pegmatites.Possible equivalents to the associations well as in differing mineralogy from one part of the describedhere are the AlrSiO'-garnet (rich in alman- pegmatiteto another. dine and spessartine)-chrysoberyl-quartz assem- The textures involving cordierite, kyanite, and blages reported from aluminous pegmatitesformed some biotite imply that these ninerals formed after at lower temperatures(Jacobson and Webb, 1946,p. the crystallization of the assemblagesinvolving su- 27; Beus,1966, p. 32; Okrusch,1972).However, the rinamite and taaffeite.They may be related to retro- garnetsin the Antarctic pegmatitesare richer in py- grade metamorphism associatedwith the tectonic rope and poorer in spessartinethan most pegnatitic zones and later pegmatites,although the cordierite garnets, and are associatedwith minerals having and biotite microveinletscould have formed during a greater Mg/Fe ratios than garnet. late, water-rich stage in the crystallization of the Another possible indication of the unusual Mg- early pegmatites. rich bulk compositionis wagnerite,(Mg,Fe)rPOnF, a Possibletemperatures and pressuresof crystalliza- mineral which would be expectedin magnesianbulk tion of these pegmatitesare constrainedby the ab- compositionswith an excessof phosphorusover cal- senceof primary cordierite and kyanite and by the cium (Sheridan et al., 1976).In some parageneses' presenceof sillimanite-orthopyroxene-quartz;they wagneriteappears with minerals rich in magnesium, are estimated to be be 800-9000c and 7-8 kbar e.g., ferroan magnesite in quartz-carbonate veins (Grew, 1980b,Fig. 5). Partial pressureof water must near Werfen, Austria (Hegemann and Steinmetz, have been sufficientlylow for the associationsillima- 1927), and phlogopite-enstatite near Kragery' nite-orthopyroxene to be stable (Newton, 1972). (Bamble),Norway (Brlgger and Reusch,1875; Neu- Comparable physical conditions are indicated for marrn et al., 1960), while in others, it is associated sapphirine-bearingquartz granulites, which are with magnetiteor ilmenit/ €.9.tnear Kragerf (816g' found in the country rocks of the pegmatitesat both ger and Reusch, 1875) and in Bavaria (Propach, localities.Sapphirine in the granulites at "Christmas 1976).Possibly low calcium and high fluorine con- Point" (e.g.,sample 2282G) has successivecoronas of tents are more i.mportantthan high Mg contentsfor sillinanite (containing minor corundum) and ortho- wagneritestability. In any case,the diversity of wag- pyroxene.These textural relationshipsimply that an nerite paragenesesimplies that this mineral is stable early-formed sapphirine-quartz associationreacted over a wide range of pressure-temperaturecondi- to form sillimanite + orthopyroxene + corundum. tions, and that its scarcity is more likely related to Theserelationships are similar to thosein the Wilson compositionalfactors or failure of identification. Lake, Labrador, sapphirine-quartz rocks illustrated Origin of the berYllium by Chatterjeeand Schreyer(1972, Fig.6) exceptfor the presenceof corundum. The high temperaturesof Beryllium mineralization in granulite facies ter- formation and absenceof beryl, kyanite, and mus- rains is rare. To my knowledge, the only other re- covite imply that the beryllium mineralization in the ports of such mineralization are the two taaffeite oc- early pegmatitesis unrelatedto the later pegmatites. currences in Australia and the three surinamite In the later pegmatites,beryl and rare beryllian so- occurrences,a5suming these surinamites, like the dian cordierite (e.9.,22828) are the only beryllium Antarctic surinamite, contain significant beryllium' minerals present; kyanite and muscovite accompany The field and mineralogical evidence relating to the 1032 GRE}I: SURINAMITE, TAAFFEITE, BERYLLIAN SAPPHIRINE

origin of the beryllium minerals and their host peg- The partial pressureof water (and fluorine?)in re- matitesin Antarctica is therefore of interest. sidual fluids from a charnockitic pluton may have The petrologic considerationsdiscussed above, U- been sufficient to transport beryllium, but not to Pb isotopic data on the early pegmatites(Grew and hydrate the sillimanite-orthopyroxene assemblageto Manton, 1979),and U-Pb isotopic data on the meta- cordierite at the high ambient temperatures during morphic country rocks (W. I. Manton, personalcom- emplacement.Only after pegmatiteemplacement, as munication, 1980)indicate that pegmatite emplace- temperaturesdecreased, did the high-temperaturesil- ment and the granulite-faciesmetamorphism of the limanite-orthopyroxene-surinamiteassemblage react Napier complex were roughly coeval. to form beryllian cordierite, and the fractures in the Sheratonet al. (1980,p. 6) suggestthat the early rock flll with biotite. pegmatiteswere "probably derived by local mobili- The CaseyBay beryllium paragenesesindicate the sation" of the country rock. Some of the early peg- possibility of beryllium mineralization associated matites, such as the irregular massesassociated with with charnockitic plutonism in granulite-faciester- boudinage (Grew and Manton, 1979),may have a rains. Such mineralization may have been over- non-magmaticorigin. On the other hand, the cross- looked in most studiesof granulite-faciesterrains, for cutting planar veins and podiform pegmatites are the more coillmon and easily recognized beryllium more likely of magmaticorigin; theseare indicated in minerals such as beryl may not be present.Taaffeite Figure l. Evidencefor this origin is found in the con- and surinamite, which may be the principal beryl- tact aureoles,which di_fferfrom the contact effects lium minerals in these deposits,could be confused around non-magmaticpegmatites described by Ram- with chloritoid or sapphirinein the field. More anen- berg (1956,p. 199),and the presenceof the beryllium tion should be devoted to the pegmatitesassociated minerals. It could be argued that the beryllium in with charnockitic plutons; these may reveal pre- these minerals originated in the country rocks, but viously unknown geochemical features of the concentrationsof beryllium in sedimentaryor meta- charnockitic suite. morphic rocks (other than in the contact aureolesof pegmatites) are exceptional. Moreover, were rocks Acknowledgments with above average Be contents (of which sample 2045A may be an example)abundant in the Napier I thank the Antarctic Division of the Department of Scienceand the Environrnent, complex, there is no obvious mechanism for trans- Australia, for enabling me to participate in thc Australian National Antarctic Research porting and concentrating Expeditions during the beryllium under granulite- 197'l-78and 1979-80field seasons,and for providing logistic sup- facies conditions. Aqueous fluids are generally be- port for my field work. I alsothank M. Sandifordand C. J. L. Wil- lieved to provide such a mechanism,but it is doubt- son of the Departmentof Gcology, University of Melbourne, for ful that aqueousfluids were presentin the host rocks providing me with scveral samplesof the latcr p€gmatites and for inviting join point." at the time of the granulite-faciesmetamorphism. mc to them in field work on "Christmas an invitation which led to my discoveryof the mincrals describedin Fluid inclusion studiesin other granulite-faciester- this report. rains suggestCOr-rich compositionsfor such fluids I thank J. W. Sheratonfor providing unpublished information (e.9.,Weisbrod et al.,1926),and the mineral assem- on localities of chamockitic and anorthositic rocks in Endcrby blagesof the Napier complex granulite-faciesrocks Land, and E.W.F. de Roever,for unpublisheddata on surfuramite. I thank J. S. White imply P",o ( P,o,.r(Sheraton et al., 1980: and R. V. Gaina for arrangingthc emission Grew, spectrographic analyscsand J. R. O'Neill, the water 1980b). Consequently, analysis. a non-magmatic source for Commentsby W. A. Dollase,P. C. Grew, P. B. Moore, and G. beryllium in the two pegmatitesappears unliksly. R. Rossman on an earlier version of this manuscript are much ap- A possiblesouroe of some of the early pegmatites preciated. is a charnockitic plutonic rock related to the ortho- pyroxene-bearing granodiorite and granite reported References by Ravich and Kamenev (1975,p. a9e and Sheraton Anderson,B. W., Payne, et al. (1980)from Tange Promontory C. J., and Claringbull, c. F. (1951)Taaf- 00 km west of feitc, a new beryllium mineral, found as a cut . Mincr- "Christmas Point") and other parts of the Napier alogical Magazine,29, 765-7 7 2. complex(Figure l). In the MusgraveRanges of Aus- Beus,A. A. (1966)Gcochemistry of Bcryllium and Genetic Types tralia, a plutonic rock of charnockitic affinities, the of Beryllium Deposis. Freeman,San Francisco. Ernabella Adamellite, is believed to be the source of Br6gger,W. C. and Rcusch,H. H. (1E75)Vorkommen des Apatit beryllium in taafeite in Norwegcn. Zcitschrift der Deutschen geologischen Gcsell- at this locality (Hudson e/ a/., schaft,27, &6-702. re67). Ccrnf, P. and Povondra, P. (1966) Beryllian cordierite from GREW: S TJRI NAM ITE, TAAFFEITE, BERYLLIAN SAPPH I RI N E 1033

V€tn6: (Na,K) * Be + Al. Neues Jahrbuch fiir Mincralogie no. Cl2. International GeologicalCotrgtlss, 2lst Session,Nor- Monatshefte, Jahrgang 1966,X-4. den 1960,l8 p. hith- Chatterjee,N. D. and Schreycr,W. (1972)The reactioncnstatitcs" Ncwton, R. C. (1972)An expcrirncntaldetermination of the + cillirnanite a srpghirino$ + qurrtz i-n the syetcra MgO- pressure stability linits of magnoden oordioritt undcr rvet rnd . Al2O3-SiO2. Contributions to Mincralogy .,rd Pctrology, 36, dry conditions.Journal ofGeology, E0,t9E-420. l'. 49-62. Okrusch, M. (1971) Zur Gencsevon Chrysobcryll- und Alexan- Deer, W. A., Howic, R. A. and Zussman"J. (1978)Rock-Forming drit-Lagerstdtten. Zeitschrift der Deutschcn Gemmologischen Minerals, Vol. 2A, Single-Chain Silicatcs (Second Edition). Gesellschaft.Jahrgang 20, Nr.3, ll4-124. Wiley, New York. Palachc,C., Berman, H. and Frondel' C. (1944) The Systemof Ellis, D. J., Sheraton,1. 1ry.,Fngland, R. N. and Dallwitz, W. B. Mineralogy, Vol. l, Elements,Sulfides, Sulfosalts, Oxides (Sev-. (1980) Osumilite-sapphirlne-quartz granulites from Enderby enth Edition). Wiley, New York. Land Antarctica-mineral assemblagcsand rcactions. Contri- Propach,G. (1976)Wagnerit von Bodenrnais(Beyerischer Walil) butions to Mincralogy and Petrology, 72, 123-143. Neues Jahrbuch ldr Mineralogie Monatshcfte.Jahrgang 1976' Grew, E. S. (1978) Petrologicstudy of tle granulite-faciesmeta- 157-159. morphic rocks of Enderby Land, East Antarctica, witl the Aus- Ramberg,H. (1956)Pegmatites in West Greenland.Bulletin of the tralian National Antarctic Rcsearch Expedition (ANARE), Geological Society of Americn" 67, 185-214' 1977-78.Antarctic Joumal of the U.S., l3(4), 2-3. Ravich, M. G. and Kamencv, E. N. (1975)Crystallinc Basement Grew, E. S. (1980a)Petrologic studies in Enderby Land with the of the Antarctic Platform. Wilcy, New York. Australian National Antarctic Research Expedition, 1979-80. de Roever,E. W. F., Kiefl C., Murray, E.' Klein' E. and Drucker' Antarctic Journal of thc U.S., l5(5), a0-+9. W. H. (19?6)Surinamite, a new Mg-Al silicate f,rom the Bak- Grew, E. S. (l9E0b) Sapphirine + quartz association from Arch- huis Mountains, western Surinam. I. Description' occutrenoe' ean rocks in Enderby Land, Antarctica. American Mineralogist, and conditions of formation. Amcrican Mineralogist, 6l' 193- 65. 821-836. 197. Grew, E. S. and Mantor5 W. I. (1979)Archean rocks in Antarc- Schreyer,W., Gordillo, C. E. and Werding, G. (1979)A new so- tica: 2.5-billion-year uranium-lead ages of pegmatitesin En- dian-beryllian cordierite from Soto, Argentina, and thc rcla- derby Land. Science,2M,43-445. tionship between distonion index, Be content, and statc of Hegemann, F. and Steinmetz, H. (1927) Die Mineralglnge von hydration. Contributionsto Mineralogy and Parology, 10,421- Werfen im Salzkammergut. Centralblatt ftir Mineralogie, Geo- 428. logie und Paleontologie. Abteilung A: Mincral,ogie und Petro- Sheraton,J. W., Offc, L. A., Tingey, R. J. and Ellis' D. J. (1980) graphie.Jahrgang 1927, 45-56. Endcrby Land, Antarctica-an unusual Precambrian high- Higgins, J. B., Ribbe, P. H. and Hcrd, R. K. (1979)Sapphirine L grade metamorphic terrain. Joumal of the Geological Society of Crystal chemical contributi,ons. Contributions to Mineralogy Australia,27,l-18. and Petrology,68, 349-356. Sheridan,D. M., Marsh, S. P., Mrose, M. E. and Taylor' R. B' Hudson, D. R., Wilson" A. F., and Threadgold, I. M. (1967), A (1976) Mineralogy and geology of thc wagnerite occurrence on new polytype of taaffeite-a rare bcryllium mineral from thc Santa Fe Mountain, Front Range, Colorado. U.S. Geological granulites of central Australia. Mineralogical Magazine, 36, Survey ProfcssionalPaper 955, 23 p. 305-310. Teale, G. S. (1980) The occurrenceof hdgbomite and taaffcitc in I Jacobson,R. and Webb, J. S. (1946) Thc pegmatitesof ccntral Ni- spinel-phlogopit€ schist from thc Mount Painter Province of geria. Gcological Survcy of Nigeria Bullctin No. 17. South Australia. Mincralogical Magezine,43, 575-577 . Kamenev, Ye. N. (1979) Drevncyshaya metamorficheskaya tol- Weisbrod,A., Poty, P. and Touret, J. (1976)Les inclusionsfluides shcha Kholmov Fayf (Antarktida). Antarktika Dollady Ko- en g6ochimie-p6trologie: tendancesactuellcs. Bulletin dc la So' missii, 18, ll-19. Nauka, Moscow. ci€t€ frangaise de Mindralogie et de Cristallographie' 99' 140- Kozhevnikov,O. K., Dashkevich,L. M., Zakharov, A. A., Kasha- r52. yev, A. A., Kukhrinkova, N. V., and Sinkevich, T. P. (1975) Wilson, A. F. and Hudson, D. R. (1967)Thc discoveryof bcryl- granulitcs thc Musgrave First raafeitc [sic] fnd in the USSR. Doklady Akadcmii Nauk lium-bearing sapphirinc in the of SSSR,224, l-2lu.^l2l(transl. Doklady Akad. Nauk SSSR,224, Ranges (Central Australia). Chemical Geology, 2' 2W-215. 1399-1,001,1977). Woodford, P. J. and Wilson, A. F. (1976) Sapphirine, hdgbomitc' Moore, P. B. (1976) Surinamitc a new Mg-Al silicatc from the kornerupine, and surinamite from aluminous granulitcs, north- Bakhuis Mountains, wGstemSurinam. II. X-ray crystallography eastern Strangways Range, ccntral Auctralia. Neucs Jahrbuch and proposcd crystal structurc. American Mineralogist, 61,197- fiir Mineralogic Monatshefte, Jahrgang 1976' 15-35. 199. Ncumann, H., Jdsang,O. and Mortoo" R. D. (1960)Mineral oc- Manuscript received,November 24' 1980; cuneloes in southcrn Norway. Guidc to excursionsno. Al5 and acceptedfor publbation, Februry 5' n8l.