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Home , Inyoite, Ulexite

Canndtan Mineralogist Vol. 13, pp. 370-376 (1975)

HOWLITEAND UTEXITEFROM THE CARBONIFEROUSGYPSUM AND ANHYDBITEBEDS IN WESTERNNEWFOUNDLAND

V. S. PAPEZK Department ol Geology, Memorial Llniverslty of Newfoundland, st. John's, Newfoundland

AND C. C. K. FONG,! DevelopmentDivision, NewfoandlandDepartment ol Mines and Energy, St. I ohn's,N ewfoundland

Ansrnect forme de nodules compos6s en forme de fram- boises de 0.5 d, 2 cm de diamdtre; elle est com- The Carboniferous anhydrite and beds pos6e de minces cristaux en plaquettes d,une iq southwestern Nevrfoundland contain small longueur de moins de 0.1 mm avec des plans (100) quantities of (NaCaBrOr.8HzO) and how- pro6minents. Ces deux min6raux ont aussi 6t6 trou- Iite (CarSiBsOr(OH)u). The ulexite occurs as ir- v6s dans deux r6gions non-localisdes auparavant de regular patches l-3 cm in diametero consisting of la Nouvelle-E le gisement Pb-Zn de Gays white fibrous crystals; the forms composite River et une carridre de gtr4rseprbs de Milford. La framboidal nodules about 0.5 to Z cm in diaieter, howlite semble avoir 6t6 form6e d'un gel; la forrra- consisting of thin platy crystals less than 0.1 mm tion des borates 6tait contemporaine avec la pr6ci- long with prominent (100) planes. The two min- pitation de sulfate de calcium. erals were also found at two localities in Nova Sco- La pr6sence des min6raux de borate (en petites previously reported - the Gays River !p _not quantit6s) semble 6tre courante dans I'anhvdrite Pb-Zn deposit and a gypsum quarry near-Milford. et le g;4pse du Bassin Carbonifdre des provinces de The howlite is believed to have been formed from I'Atlantique; par contre on ne rapporte aucune a gel; the formation of the borates was contempo- autre pr6sence similaire ailleurs pour f instant. Irs ran€ous with the precipitation of calcium sulphate. quantit6s normales de bore dans l'eau de mer sont Borate , in small quantities, seem to be suffisantes pour expliquer la quantit6 de borates common in the anhydrite and gypsum of the Car- otserv6e. Il est fort possible que de semblables pe- boniferous Basin of the Atlanfic provinces. but no tit€s quantiti6s de borates soient pr6sentes dans reports of similar occlurences elsewhere are known d'autres gisements d'anhydrite-gypse mais elles au- at this tim:. The normal amounts of in sea- raient 6t6 n6glig6es. Si elles sont vraiment absentes watet are sufficient to account for the observed de d'autres lits marins 6vapor6s, Ia diff6rence peut quantrty of borates. It is possible that similar small 6tre caus6e par les variances dans le pH, la solubi- guantities of borates are present in other anhvdrite- lit6, le taux d'6vaporation, etc. phtt6t que par gypsum deposits but have been overlooked. la If they pr6sence ou I'absence are truly absent from marine des sources ext6rieures de beds else- bore. where, the difference may be caused by differences (fraduit par le journal) in pH, solubitty, rate of evaporation etc. rather than by the presence or absence of external sources of boron. INrnopucrroN

The occurrence of borate minerals in the Rfsunri g)apsum deposits of Lower Carboniferous (Wind- - Les lits de g:ypseet d'anhydrite de la p6riode Car- sor) age in the Atlantic Provinces of Canada bonifdre du sud-ouest de Terre-Neuve contiennent was first dissovered more than 1O0 years ago petites de quantit6s d,ulexite (NaCaBoOr.gIIgO) et de by Henry How, then Professor of Cnemistrv howlite, CafiB6Or(OH)6. L,ulexite se pi6sente and Natural History at King,s College in Wind- sous forme de taches irr6gulidres de 1 tr f cm de sor, Nova Scotia. How described oonatro-boro- diamdtre; celles-ci sont composdes de cristaux " (now ulexite, NaCaBsOe.8HzO) from blancs fibreux; la howlite, elle, se pr6sente sous "u Llq of a very extensive formation of gypsum at Windsor, on the Clifton estate, lateiy the properfy of Judge Haliburton', (IIow 1g57), *Publication authorized by the Director of Min- and "cryptomorphite" (now ginorite, CaaBtaOu. eral ,.the Development Division, Department of Mines 8HeO; Hey & Bannister 1952) from same and Energy, St. John's. guarr)', at a distance of about 100 vards and 37A 37L HOWLITB AND ULE)CTE FROM CARBOMFEROUS GYPSUM AND ANIIYDRITE BEDS 'gypsum at about 20 feet lower level" (IIow 1861). Both renpe of ulexite and from the minerals were associatedwith , NagCa- quarry at Hillsborough, south of Moncton, New (SOa)2. Later, How reported a new mineral lirunr*i"t (Walker 1921). More recently, Sa- which he named "silicoborocalcile" (now how- bina (1965) found crystals of howlite up to lite, CaaSiBsO'(OH)u) ftom a locality at Noel, 1.3 cm long, associated with fine-grained how' Hants Co., Nova Scotia, "in nodules sometimes lite and aanfuritg in gypsum near Iona, Cape as large as a man's heado'QIow 1868, 1877). Breton Island (see Fig. 1 for all localities). How's original localities were later re-exam- In this paper, we report for the first time the ined and his dissoveries confirmed by N. R. occurrenc€ of howlite and ulexite in the Lower Goodman, who also found howlite as nodules Carboniferous evaporite deposits in western up to 5 cm in diameter at Wentworth, Hants Newfoundland. In addition, during a recent field County, as "small nodules" at Cheverie (Ilants trip organized by the Nova Scotia Department Co.) and Bevis Point (Victoria Co., Cape Bre- of-Mines, we found howtte and ulexite in anhy- ton Island), and as nodules more than 15 cm in drite in drill-cores from the newly explored km diameter "in a clay horizon in the National Gays River Pb-Zn deposit about 8 southeast Gypsum Co. quaries at Dingwall (Cape Breton of Shubenacadie, and ulexite nodules in the Island)". Goodman further reported ulexite at large g1rysum quarry near Milford, both in Wentworth, Dingwall, Bevis Foint, and at White Halifax'Co., Nova Scotia. We further obtained Head near Cheverie, and in addition described from Mr. W. Lewis, Senior Geologist of the tb€ occurrence of danburite (CaSizBeOe) at Fundy Gypsum Co., a specimen. of gypsum White ltread and "in the shore outcrop 2 miles from- liliJborougb, New Brunswick, contain' SW of Iona, Victoria Co. (Cape Breton Island)", ing several ulexite nodules, thus confirming and inyoite, CazBoOu'13HrO, ps "beautiful Walker's earlier report. It is clear therefore that solourless crystals" from the Wentworth area, borate minerals, in small quantities, are wide- Hants Co., all in Nova Scotia (Goodman 1957). spread in the Lower Carboniferous evaporite Earlier, T. L. Walker had reported the occur- basin of the Atlantic Provinces.

I FLAT BAY a Ftsct€LL's ERoo( 3 DITOfALL /t l€VlS FoNr 5 tot{A 6 CAYSRIVER - I]t- 7 |TLFORO \ I t{oEL ) €uLF or 9 UEIITUORTH il ro flt{oson II CHEVENIE f gr. LArtExcE t2 HILLSo0BOICtl { ffi-* c tt lnETd @ftffiffi[sr" 6\ aonfg LocALtrlEs / Iuttt # (c'

Frc. 1. Borate localities in tbe carboniferous basin ol the Atlantic region. 372 THE CANADIAN MINERALOGIST

BonerBs m NpwrouxoreNo Brook and in the Flat Bay gypsum quarry. The Geological setting rocks of the Anguille and Codroy Groups are folded here into an elongate antiitine, tne axis The Car,boniferous rocks of Newfoundland of which runs NE-SW, almost parallel to the form the northeasterly part of a large Carboni- coastline. A nearly continuow section of these ferous basin extending across the Gulf of SL beds is exposed in Fischell,s Brook. The An- Lawrence through Prince Edward Island ro guille Group is here represented by about 200 New Brunswick and Nova Scotia. In New- ft. (61 m) of sandy conglomerate that grades foundland, Carboniferous rocks are found in towards the top of the group into a lO-foot two separate basins within a relativelv narrow. (3 m) quartzitic sandstone. This is conformablv elongate, northeasterly-trending belt in thr; overlain by a @-foot (18 m) thick formation western part of the island, extending from Cape consisting of alternating limestone and shale, Anguille in the southwest to White Bav in the the Ship Cove Formation, which marks the base northeast. Rocks of the southwesterlv barboni- of the Codroy Group. The Ship Cove Forma_ ferous basin are exposed along the slore of St. tion, is followed by an approximately 3000_foot George's Bay and in the adjacent Anguille sequence of red, finely cross- Mountains, forming a belt 2O-25 J9l5_ 1n) -thick km wide and bedded siltstone, sandstone, green shale and about 100 km long; they are separatedby a ma- , overlain by a 1200-foot (366 m) se_ jor fault of regional extent from the igneous quence of alternating dark grey shale and car_ and metamorphic rocks of the Long Range bonate; the carbonatesconsist of marine fossili- Complex to the southeast. ferous limestone, algal limestone, small algal The Carboniferous sediments of this basin reefs and red, dense, non-fossiliferous dolomite. have been suMivided into three stratigraphic The evaporite horizons in the Fischell,s Brook units. The lowest, the Anguille Group, consists section attain a thickness of 150 tt. (46 m) and of a thick s€quence of terrestrial clastic sedi- 200 ft. (61 m) respectively. Howlite was found ments, mainly sandstone, shale and conglo- in the higher of ths two horizons, which crops merate; it is of Mississippian age, and is be- out by the railway bridge on the southern bank lieved to be equivalent to the Upper Horton of the stream (48o18,30,,I{,58"403Cl^W) in a Group of Nova Scotia. The middle unit. the vertical cliff. The outcrop consists of blue anhv- Codroy Group, comprises limestone, siltstone drite at the cliff base and white gypsum on toiU and thick Ca sulphate beds, followed by silt- the anhydrite is bedded, with grey mud stringers stone, sandstone and minor limestone of non- marking the beddinrg. origin. The Codroy Group, 1_a-ri1e of Upper The howlite appears as white nodules in the Mississippian age, has been correlated with ihe anhydrite; being somewhat more resistant to Windsor Group of Nova Scotia. The upper erosion than the anhydrite, the nodules are unit, mainly Pennsylvanianbut including loiiily most conspicuous on weathered surfaces. Most rocks of Late Mississippian age, is thi Bara- of the nodules are from 0.5 cm to 1.5 cm in chois Group, consisting of sandstone, siltstone diameter and have a characteristic crenulated and conglomerate with minor limestone and surface-resembling a cauliflower; when clean, some coal beds. It is equivalent in part to the the surface has a vitreous to pearly luster ,(Fig. C_ansoGroup and partly to the pictou Group of 2,.3). Although the nodules are small, they are Nova Scotia (Riley 1962). fairly abundant at this locality - about Evaporite sequences, one comprising mainly an- nodule per square foot of exposed surfrice (10.i hydrite and gypsum with a few salt beds, are I I nodules per squre meter). The white gypsud confined to the Codroy Group. The occurrences In the upper part of the cliff is inaciessible, of gypsum and at numerous localities within the thus the total thickness of the :h'owlite-bearing area have been described by several authors horizon is .not known. So far, howlite is the (e.9. Hayes & Johnson 1938; Baird L9S7). A only boron-cslf4ining rnineral found at this large gypsum quarry south of Flat Bay, owned Iocality. by the Flintkote Co, of Canada, is now in oper- The most abundarit in the Flat ation; in 1973, it produced about 735,000 ions Bay gypsum quarry is ulexite, which forms of gypsum (Stonehouse1973). ir- regular to oval masses1-3 cm across, consisting of very fine felted fibers. The ulexite masses Borate localities aro somewhat crumbly and less resistant to weatherin! than the howlite noades Aescribed Small quantities of borate minerals have been above, but are conspicuous on lisht found so far at two localities srev within the svD- weathered surfaces by their pure whiie sum deposits in Nen'foundland - at Fischili,s Fig. a); tleir main host iosk is gypsum,"rfu; but HOWLITB AND IJLEXITE I1ROM CARBOMFEROUS GYPSUM AND AN}IYDRITE EEI}S 373

(3) howlite lodule F.ras. 2-7. (2) Howlite nodules from Fischelfs Brook, soutlw€_stemNewfoundland; :: Dinet;aU, Nova Scotia (don. by E. R. W. \ieale); (4) ulexite patches in weathered*gy,1xum' from Flat Bav; ft;trailq;;y; s.'w. N.*ti-dhn& (5) esalning nqlcrolcopeimage oj ulexite, "1""1to" (7) scauing electron.micro- (;j .d"fi,g ei&tton -i"io.*p. imaie'o'f ,howlite, Fischelfs Brook; scope image of single crystal of howlite, Fischell's Brook' 374 TIIE CANADIAN MINERALOGIST

some have been found also in the underlying overlapping bundles. This simple habit of ulex- anhydrite. The occunence of ulexite is re- ite, with its characteristic square to rectangular slricted to some parts of the quarrn suggesting cross-sections formed apparently by equal or that the mineral is concentrated within a reli- almost equal development of two pinacoids in tively narrow stratigraphic horizon; but as the tle vertical zone, differs somewhat from. tle structure of the evaporite beds in this area, highly modified crystals reported by Murdoch which may be very comFlex in detail, has not (194O, Figs. 3 to 5). The crystals appear to be yet been worked out, no more precise statement terminated by simple pinacoidal planes, but can be made at this time. theso may be planes or sur- No howlite has been observed bv either faces rather than true crystal terminations. Con- author in the surface exposures of the Flat Bay siderable difficulties were encountered in ob- gypsum quarry, but a short piece of a drill- serving ulexite crystals at high magnifications, coro from the quarrn collected by C. Fong, probably due to their transparency combined contains a fypical howlite nodule 1.5 cm in with a relatively loose packing. diametel, enclosed in anhydrite. The presence of the silicoborate in the Flat Bav area is thus X-Rey DrrrnecrroN Srupy established, but a more systematic search of both surface exposures and drill-core will be The borate minsl4ls from the Newfoundland needed before the distribution of the borat€ localities were studied by standard methods on minerals can be determined. a Philips .r-ray diffractometer, together with a specimen of howlite from Dingwall, Nova Sco- Cnysrer, Hlnrr or Howr-rre errro Ur.B:mr tia, and a specimen of porcelaneous howlite from California, both kindly provided by G. R. Several typioal nodules of howlite and ulexitc Grantham, Curator of Geology of the Nova from various localities were examined bv scan- Scotia Museum in Halifax. Cell dimensions for ning electron microscope (Cambridge Scientific the two minerals were calculated by R. G. Instruments "Stereoscan', Mark 24, operated Cawthorn of Memorial University from tie by Dr. V. C. Barber, Deparhent of Biology, diffractometer data, using a computer program Memorial University of Newfoundland). of Appleman et aI. (1972). The howlite nodules were found to consist of The .r-ray study shows a close similarily 6e- tightly-packed thin platy crystals. The size of tw€en specimens of howlite from Fischell's the crystals ranges from 10 to about 50 microns. Btook, Dingwall and California, and an equally In the nodules from Fischell's Brook and Dino- good correspondence between the investigated wall, the average size is about 30-40 micro-is howlite and ulexito and published .r-ray data on and the largest crystal observed was 11O mi- both minerals (Murdoch t94O, 1957; Clark & crons long; in dense porcelain-like nodules from Christ 1959; Finney et al. 197O; Stojanovic California tle crystals are smaller, about 10-20 1967; Traill 1969). The narrow range of varia- microns on the average, but their habit and tion can probably be ascribed to the pudty of parallel packing are very similar to the Cana- chemical composition of the borate minslals, dian specimens. The thickness of the plates with only a small range of substitution in the ranges from 2 to about 6 microns ,(Fig. 6). One lattice. of the nodules from Fisshell,s Brook disaggre- A much greater discrepancy was noted in gated in water to a fine white powder. Scanning tho relative intensities of the diffraction peaks electron. microscope showed that this powder of howlite from different localities Cfable 1), consisted of single crystals and small crystal This is particularly evident when our results aggregatesoJ howlite (Fig. 7), closely resembting and those given iq several previous publica- an illustration of a "typical srystal habit of tions are compared to intensities calculated from howlife" presented by Murdoch (tgSl, p. SZt); strustural factors (Smith et al. t973). The ano- platy the habit of the mineral is the iesult of a maly consists mainly of the enhancement of shortening along the crystallqgraphic c-axis and the &00 peaks and a relative suppression of tle corresponding development of a prominent others. This appears to be related to the mor- (10o) face (Murdoch 1957). phology of the crystallites with the prominent The "cottonbdlls" of ulexite consist of thin (1@) face (FiS. 6, 7) and possibly- to (100) needle-lik9 crystals, some with almost square cleavage. Although the anomalous variation in cross-sections, otherr somewhat flattened. The peak intensities may thus be caused simply by crystals are about 1-3 microns thick and from prderred orientation produi:ed during the 50 to-80 iack- microns long (Fig. 5); they are ar- ing of diffractometer holdere, it persisted in our ranged in loosely-packed, randomly-oriented patterns even after its cause had been identified BEDS HOWLITB AND I]LEXTTE FROM CARBONIFEROUS GYPSUM AND ANIIYDRITE 375 and TAELE I. VAN1ATIOII II{ LIIIE INIEIEITIES IN POMER PATTERN OF HOI|.IIE the matrix of conglomerates, sandstones same sequence.Stojanovic (1967, a(i) avg. (a) (b) (c) (d) (e) (f) (s) tuffites of the p. that tle howlite is of pneumato- 12.4 54 52 33 40 60 28 40) believes 6.19 100 97 8l I00 90 I00 100 lytic origin. 4.35 r . t 30 r 19 - 4.12 9l 100 @ 40 100 20 The oicurrence of howlite and ulexite in ma- 3.89 v 15 44 80 l8 95 90 3.09 gtl 93 100 90 75 65 80 rine evaporites, particularly in anhydrite and 3.01 23 .25301637 2.94 63 86 8l 40 50 28 gypsum deposifs, thus appears to b-e restricted .r-t29 40 2.90 '1716 the Atlantic prov- 2,78 rl.t25 io the Carboniferous basin of 2,66 ' . r 20 | ?7. The problem is whether the 2.47 37 4938-50 inces of Canada. 2,44 ' ti40t23 gypsum deposits . I absenceof borates from other 2.16 '1323 10 2,07 . 23 50 ' 19 elsewhere is real, in which case special condi- 2.06 35 4436-50t 2.03 23 *25701041 tions should be sought for the Carboniferous 2.0t 18 29 29 20 20 2.00 20r- evaporites of Atlantic Canada, or whether small 1.97 r r1301018 present in a similar.set- 1.92 r 143130t quantities of borates are 17016 25 27 50 16 ting at other localities but have been either - llne absent * llne pr*ent but rct mng tie l5 stmngst llns overlooked or not reported in literature. (a)Flschell's Brmk, ttsfoundland (thls study); (b)Dln$all, Nova scot{o surface of Sc6tta (Ats study); (c)'Callfonlao porclon46 hqllte (thls stldyli The nodular form and framboidal (d) ilurdoch 1957,'JcPDsCari 10-410; (€) stoliloYlc 1967, JCPDSCard l8- formation from a gel, prob- 618; (f)Sdtn et dL. 1973i (s)Tralll 1969. the howlite suggest ablv in the form of coalescing globules. At fisthetl's Brook, where the silicoborate nodules and an attempt had been made to correct it; found in relative abundance,the sulphate se- even repeated sareful grinding and repacking are quence is interbedded with shalesand siltstones, (by the back-filling method) did not succeed in colloidal silica may be assumed to be bringing the observed intensities appreciably *here in contrast, siliceous beds are closer to the calculated values. Similar variation freely available; in the Flat Bay area where howlite is is evident in powder patterns published by lacking the main borate minerals is ulexite. others. Of the five strongest lines in eac pow- rare and -h of composite globules in the pattern. two (6.19 and 3.09A) are The formation der onlv lateral mobility of the comrion to-ail s6ven patterns compared in Ta- colloidal state assumes ulexite probably crys- ble 1. As this enhancement effest could have gel. Although the fibrous solution, the concentra- adverse influence on a routine identification of talized directly from a fibers in small irregular patches howlite by any method using a limited number tion of ulexite requires some mobility of the cry-stals' of "strongest" lines, it should be kept in mind. again fhrn *"- postulate that the formation of the borate minerals was contemporaneouswith the DrscusstoN precipitation of tbe sulphate. The question- of Although the presence of small quantities of which of the two Ca sulphates formed first does borate minerals in the gypsum deposits of No- not seem relevant to this discussion. va Scotia has been known for a long time, it is Simple calculations based on the averagecom- interesting to note that no similar occurrences position of sea-water (SO4 0.264979, H.fO" in other localities in North America or else- O.OOZ|%; Mason 1966, p. 194) indicate that where have been roported in any major geo- the normal amounts of boron in sea-wat'er ate logical publication. (Ihe authors would wel- more than sufficient to account for the occur- come any reference to published papers that rence of borates in the'observed amounts in the they may have missed). Both ulexite and how- marine evaporites of the Atlantic provinces. lite are well-known constituents of the borate .In view of this, and of the wide distribution of deposits of the western USA, but these deposits small quantities of borates throughout the Car- of are part of a continental evaporite sequence in boniferbus basin, no special external source which the boron is betrievedto be of volcanic the boron needs to be sought. This would sug- (fumarolic) origin (Foshag L92I; Schaller 193O). gest further that similar small quantities- of A little-known Yugoslav occurrence of a com- borate minerals ought to be present in anhydrite pletely different type, described by Stojanovic and gypsum deposits at other localities outside provinces. a systematic search QgAT, is located near Raska on the river Ibar, the Atiantic If about 150 km south of Belgrade. Fine-grained of such deposits shows that borates are truly white howlite forms two lenses, L0 meters and 3 absent, the difference would have to be ex- such meters long and 20-30 cm thick, lying confolm- plained by variation in other critical factors rate of ably in an interbedded sequence of volc-anics, as pH, iemperature, , and will be claitic sediments, carbonates and marls of Ter' evaporation. Clearly, further work tiary age; locally the mineral is found also in needed to solve the Problem. 376 THE CANADIAN MINERALOCIST

ACKNOWLEDGEMENTS nite depositsof California. Econ. Geol. 16. 199- 214. We wish to thank Mr. R. G. Grantham. Cura_ GoooMaN,N. R. (1957): Gypsum tor of Geology, in Nova Scotia Nova Scotia Museum in Hali- and its associatedminerals. In The Geology fa1_ of f9I the specimens of howlite from Ding- Canadian Industrial Mineral Deposlts (M. F. wall, Nova Scotia, and from California. which Goudge et al. editors), Can, Inst. Mining & Met., were included in our study. Mr. D. B. Joigensen, Montreal,110-114. Senior Staff Geologist, U.S. Gypsum Co-.. pro- HAyEs,A. O. & JoHNsoN,H. (1938): Geologyof vided valuable information on g1psr,- deiosits the Bay St. George Carboniferous arca. Nftd. -tb Geol. Surv. in the U.S.A.; we are thankful Vfr. W. I.. Bull. L2. HEy, M. H. Berr.nsrnn, (1952): I-ewis, Senior Geologist, Fundy Gypsum & F. A. The iden- Co., tity of cryptomorphite ginorite, for interesting discussions and Mineral. and for a siecimen of Mas. 29, 955-959, ulexite from Hillsborougho New brunswick. How, H. H. (1857): On the occurr€nce Our thanks ,G. of natro- are also due to Dr. L. Berry, boro-calcite with Glauber salt in Gypsum of Quoenos University, for unpublished data on Nova Scotia.Amer. l, Sci. 24, 230-235. howlite and a copy of the piper by Stojanovic, (1861): Natro-boro-calciteand another and to our colleagues,N. p. Jamei of ihe ne_ borata occurring in the gj?sum of Nova Scotia. partment of Geology and W. D. Machin of the Amer, J. Sci. 82, 9-I3. --:-'' - (1868): Department of Chemistry, for valuable discus- Contributionsto the mineralogy of Nova Scotia. III. Tle cooperation of Dr. V. C. Barber, Dr. Borates and ottrer minerals $onq in anhydriteand gypsum.Phil. Mag. R. G. Cawthorn and Mr. J. Vahtra is grate- 98,3241. (1877): Contributions16 1[s mineralogy lrlly -acknowledged. Mr. W. March prelared of Nova Srcotia. the Mineral, Mag, L, 257-260. _phototgraphsand Ken Byrne the mai. MryoN, B. (1966): Principles of Geochemistry. We further wish to express our thanls to (3rd ed.). John Wiley & Sons, New york. Mr. F. S. Shea, Mr. P. S. Giles and their col- MunoocH, J. (1940): Crystallographyof ulexite. leagues for an exce.llent field trip to various Amer. Mtneral. 25, 7 54-762. mineral localities in Nova Scotia, brganized by (t957): Crystallographyand .r-ray meas- the Nova Scotia Department of Min&. part of urements of howlite from Califoruia. Amer. Mineral, the field expenses of the senior author were 42, 521-524. Rr!"v, C. C. (1962): by NRC Grant A-2131, which is grate_ Stephenvillemap-area, New- 9o-v-ered foundland. Geol. Surv. Can. Mem. 528. fully acknowledged. Fong,s work comfrised SenrNa,A. P. (1965): Rocks and mineralsfor the part of a geological napping project conducted collector: norfleastern Nova Sootia, Cape Bre- behalf _on of the Mineral Development Division, ton and Prince Edward Island. GeoL Sum. Can, Newfoundland Department oi Mines and Paper 65-L0. Energy. ScnAr.LER,W. T. (tS:O): Borate minerals from tbs Kramer District, Mojave Desert, California. RrrunrNcrs U.S. Geol. Surv, Prof. Paper L58-1, 137.173. SMrfit, D. K., Tervru, LowBxruurr & Resrvrusssx AppLEMAN,D. E., Evexs, H. & Hexownrnn, D. (L973): Annual Report to the Joint Committee (1972): Indexing and least-squaresrefinement of on Powder Diffraction Standards, 1973. (Un- powder diffraction data. 7J. GeoI. Sam. Com- publ. Rept.). putet Contrib. iVo. 20. Sro.reNovrc,D. (1957): Howlit iz Jarandolskog BAnD, D. M. (1957): Gypsum depositsof south- I"tourqoq baseaa. Slowlite from the Tertiary v/esternNewfoundland. In The Geology of Cana- basin of larandol). Proc, 6th Congr. Un. Geoi" dian Industrial Mineral Deposits, M. F. i3oudge Soc. lugoslavia, Skopje,vol. 3, 35-43. (In Ser. et al. editors), Can. Inst. Mining & Ma., Moit- bian, German summary). rcal, 12473A. SroNrnouse, -D, H. (1973): Gypsum and anhy- cLARtr,J. R. & CnRrsr, C. L. (1959): Studiesof drfte,Can. Minerals Yearbook197J, No.19, Min" borato minerals (V): reinvestigation of the .x- Res. Brancho Ottawa. ray crystallography of ulexite and probertite. T[.Anr., R. J. (1969): A catalogueof Canaiilian Amer. Mineral. U, 712-719. minerals. Geol. Surv. Can paper 6g45. Fl![NEt, t. J., KutdEAsAR,I., Korsrnr, L A. & Werrrn, T. L. (1921): Ulexite from the Maritime CLARK,t. R. (1970): of the provinces. Univ. Toronto Stadles, Geol. Ser. l:Z, calcium silicoborate, howtite. Amer. Mineral. 5+57. 55, 716-728. Fosgr'c, IV. F. (1921): The origin of the colema- Manuscriptreceived May 1g75,emended June 1g75.