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Home , Beryl, Calcite, Feldspar, Galena, Jasper, Labradorite

NOTES AND NEW TECHNIQUES

By Seppo 1. Lahti and Kari A. Kinnunen

St~omg&etched prismatic cystak ofyellow,, and pale bluegem have been quarried fiom a dike in Luumaki, Finland. To date, the peg- mdite has yklded about 15 kg ofgmberyl, minm amounts of&etgvade , and many varieties of qua&. lke gem fiom Luumaki are similar in gemological properties and chemical composition to other pegmatitic beryls, such as those fiom B~azt'Zand the Vkine.Lawe primary fluid inclmhs sur- rounded by mimqfracture halos may be diagnostic of the new locality.

h 1982, enthusiast Kauko Sairanen noticed pegmatite. At first the outcrop seemed promising, a outcrop near a small road in Luumaki, a com- and several gem-quality -some quite large- mune in southeast Finland. Of particular interest were were recovered; many have since been faceted (figure 1). elongated pockets that were lined with quartz crystals However, the small-scale conducted to date and contained a pale yellow transparent mineral that indicates that the gem beryl occurs sporadically, so the was later identified as beryl. Subsequent geoloac map- claim owners have continued their worlz only inter- ping showed that the outcrop represented the core of mittently. a small pegmatite dilze, which had intruded a Luumalzi is about 180 lzm northeast of Finland's coarse-grained rapalzivi (i.e., a granite that capital, Helsinki, and less than 40 lzm from the contains large crystals surrounded Russian border (figure 2).Public access to the by a shell). is possible with permission from the owners. For this Mr. Sairanen and some friends took out a mining study, we visited the site and collected specimens sev- claim in 1986 and formed a company to work the eral times during the last five years. We also studied the gemological properties of several gem beryl crystals and cut stones provided by the mining company.

AND ABOUT THE AUTHORS OCCURRENCE Although numerous complex occur in the Dr. Lahti is state geologist in the Petrology Department, and Dr. Kinnunen is speck1 research scientist in the Precambrian rocks of southern Finland, gem Department, at the Geological Survey of Finland, Espoo, Finland. have been found only occasionally. In addition to sev- Acknowledgments: The authors thank the owners of Suomen eral quartz varieties, small amounts of topaz, lun- Jalokivikaivos Oy (The Precious Stone Mine of Finland Co.)- zite, morganite, yellow beryl, and colored tourma- Matti Ung, Risto Pitunen, and Kauko Sairanen-for help and information. They also thank their colleagues at the Geological lines have been recovered in the course of feldspar Sumey: Miria Samnen and Leena Jhinen, for help with the mining (Haapala, 1966; Erametsa et al., 1973; Lahti, mineralogical studies: and Christian Backman, Riitta Juvonen, 1981; Lahti and Saiklzonen, 1986). Maja Ilmasti, and Lasse Pakkanen, for chemical analyses of the beryls. The Luumaki pegmatite is situated in the north- em comer of the large Wiborg rapaluvi granite com- Gems & . Vd. 29, No. 1, pp. 3M7 plex, which consists of several granite as well as minor 0 1993 Gemological Institute of America (some of which contains the local

Notes and New Techniques GEMS ei GEMOLOGY Spring 1993 Figure 1. This features three faceted Luumal

often called spectrolite) intrusions. The , , , and gem beryl; local- Wiborg complex covers an area about 100 x 180 lzm ly, , goethite, and are common. that extonds from southeastern Finland to nearby The bottom of a poclzet is usually covered by a layer Karelia, Riissia. The ddferent rapalzivi in the of -brown minerals and fragments loos- region vary between 1,650 and 1,700 million years ened from the walls. (My)old (Vaasjolzi, 1977);the pegmatites might be Two generations of beryl can be distinguished in somewhat younger. The Svecolzarelian , , metavolcanics, and into which the Figure 2. The commune of Luumalii, where the rapalzivi granites were intruded are 1,800-1,900 My. gem beryl pegmatite was found, is located about Geologic mapping by one of the authors (SIL) 40 km (25 miles) from Finland's border with . revealed that the pegmatite is a poorly exposed dike about 20 m wide in granite (figre3). A massive quartz core, about 10 m wide, makes up the central part of the dike. It is surrounded by thee feldspar--quartz pegmatite zones referred to here as intermediate, wall, and border. The grain size of the pegmatite increases gradually from the narrow, fine-grained border zone nearest the host granite to the quartz core. The tran- sitions between the zones are also gradual. The main minerals in the pegmatite, in addition to quartz, are reddish brown inicrocline, albite, quartz, biotite, and, locally, . The of both the border and wall zones is simple, but the intermediate zone contains a number of rare miner- als (table 1).Very large crystals of common beryl, topaz (not of gem quality), and monazite-(Ce)are char- acteristic in the intermediate zone in particular. Poclzets are abundant in the central parts-the core and interinediate zones--of the dilze; they range in diameter from several centimeters to several tenths of a meter. The pockets may contain crystals of quartz,

Notes and New Techniques GEMS & GEMOLOGY Spring 1993 Figure 3. Geologic map of the Luzlmiilii gem beryl pegma~ite.The colors repre- sent: (1) rapakivi granite, country ; (2)fine-grained border zone of the peg- matite d&e; (3) wall zone of the peg- matite; (4)very coarse in~ermediate zone of the pegmatite; (5)quarb core; (6)gem beryl quarry; and (7)larger cavities or crystal pocliets observed on the surface, partly abraded and pol- ished during glacial time. Gem beryl has been found in the pocliets within the quarry, whereas crystals of com- mon beryl sporadically occur in the intermediate zone around the quartz core. The road on the left joins the vil- lage of jumala (by the main road no. 6 i meters at Luumiiki) to the village of Tudiainen.

the pegmatite: The older is opaque, common beryl hand. They use and chisels to empty the (not gem q~~ality),and the younger is transparent, gem poclzets and then screen the clay-rich material in beryl. The common beryl is yellow, often strongly water to reveal any gem beryl (figure 6). Currently altered by hydrothermal solutions, and usually stained the pit is 20 m long, 10 m wide, and 5 m deep. and impregnated brown by compounds. The crys- Of the 15 kg of gem beryl found thus far, approx- tals of common beryl, whlch usually range from 5 to imately 40% is grade. The gem beryl usually 15 cm (up to 30 cm)in diameter, have well-developed ranges froin pale yellow to greenish yellow to yel- first-order prism faces and, occasionally, basal pinacoids lowish green; rarely, the material is a bright "- (Pitlzanen, 1991). en" yellow (figure 7). Approximately 10%-15% of Common beryl occurs in the intermediate zone of the total would be considered aquamarine, with var- the pegmatite, while gem beryl is found only in poclz- ious shades of . Although the mine owners main- ets, either associated with common beryl or embed- tain that they have not traded in treated beryl, ded in the microcrystahe reddsh quartz ()that experiments by the authors have shown that blue locally fills the poclzets and fractures (fipre4). aquamarine can also be produced by heating pale The gem beryl crystals usually range in weight green or yellow green beryl from this locality (see from a few grams to several tens of grains. The largest Ehmrooth and Tuovinen, 1989). and most attractive crystals found to date are "Mrs. Ellie" and "Mr. Jock," which weigh 450 and 950 grams, respectively. Both are high gem-quality green TABLE 1. Minerals identified in the intermediate zone of the beryl (figure 5). "Mrs. Ellie" is now in the collection Luumaki beryl pegmatite. of Finland's Central Museum of , housed in the Departinent of Geology and Mineralogy, and others University of Helsinki. K-feldspar: Margarite Quartz - Microcline lllite Monazite-(Ce) MINING AND PRODUCTION - Orlhoclase Goethite The Luumalci pegmatite is mined by a small Finnish Albite Smectite company, Suomen Jaloluvikaivos Oy, intermittent- Biotite Vermiculite ly during the summer months from May to September. Muscovite - The thrce owners have contracted with a local con- Chlorite Euxenite struction firm for help with heavier mining chores. Belyl Fluorite Topaz After blasting with forcite (a slow-detonating type of Berlrandite dynamite), the owners collect the gem material by

Notes and New Techniques GEMS B;. GEMOLOGY Spring 1993 optical absorption spectra were investigated with both a prism and a ciiffraction-grating spectroscope. Specific gravity was measured in a polytungstate- water solution. A Philips X-ray diffractometer and Debye-Scherrer camera were used in the X-ray powder diffraction analyses of the beryl samples and in the identifica- tion of associated minerals, with reference to the JCPDS (International Center for Diffraction Data) files. Unit-cell dimensions were computed from the indexed X-ray powder diffraction patterns using the computer program of Appleman and Evans (1973). The chemical composition of the gein beryl speci- mens was determined-using a combination of micro- probe analysis, atomic absorption spectroscopy (AAS), and inductively coupled plasma-atomic emission Figure 4. A 5-cm-long cigar-shaped crystal of yel- spectroscopy (ICP-AES)-at the Chemical Laboratory lowish green belyl is shown here iti the massive red- of the Geological Survey of Finland. dish brown microcrystalline quartz (jasper) in inclusions were identified by ineans of polar- which it w(zs found at Luumaki. Photo by Iari ized niicroscopy. Gelnologically characteristic inclu- Viiiitainen. sions were determined from the seven natural-color yellow and pale green beryl crystals and one heat- Facet-quahty pieces of blue, pale pinlz, or colorless treated yellow beryl specimen, following the methods topaz (0.5,-8 ct), as well as smolzy, rock crystal, brown- outhed by Gubeh~and ICoivula (1986).The 20 faceted ish green (praseolite-like),and red (ferruginous, resem- stones were also examined with the ; how- bhgfire ) quartz have also been found. In addition, ever, inost of these were clean, without any inclu- much of the quartz recovered call be used for cabo- sions. Fluid inclusions in one rough yellow beryl chons or tuinbling material. sample were studied with microscope heating and freezing stages using doubly polished thick sections, MATERIALS AND METHODS (Roedder, 1984; essentially the same techniques and The Sample. The study included about 2 kg of gem beryl rough: numerous crystals or fragments of Figure 5. These tlwee crystals are typical of the various sizes and colors-some self-collected and oth- high-qzrality green beryl recovered from the ers obtained from the mining company-and 20 Lu~~malzipegmatite. The large crystal at the rear, faceted stones of various colors that were provided known as "Mrs. Ellie," is 14 cm long and weighs by the mining company. Physical, gemological, and 450 grams. ?'--to b;. ,T-i VP“ ::'men. chemical properties were determined on seven (about 14cm) rough pieces of yellow and pale green beryl and on 15 faceted green, yellow, and pale blue stones (141.7ct). The beryl crystals studied werc typical of the locality: prismatic, usually cylindrical or cigar shaped; some were strongly etched and quite irregular in form (again, see figures 4, 5, and 7).The round or oval bril- liant-cut, step-cut, and antique-cut stones were fash- ioned in Finland (by K. Sairanen, M. Ling, and S. I. Lahti) and abroad.

Methods. Gemological properties were determined for the seven rough and 15 faceted beryls, following the routine procedures described in Liddicoat (1989)and Read (1991).Refractive indices were measured with a I Rayner refractometer with a sodium llght source, and

Notes and New Techniques GEMS & GEMOLOGY Spring 1993 Figure 7. Most gem bey1 crystals from the Figure 6. The beryl crystals at Luumaki are usually Luumaki pegmatite range from yellow to greenish found embedded in a reddish-brown clay. Here, yellow and yellowish green. The largest crystal, in the miners wash clay removed from pocliets in the the front, is 7.2 cm wide and weighs 110 grams. pegmatite to reveal any beryl crystals present. Nole the "golden" yellow crystal in the upper left. Photo by Matti Lang. Photo by Kari A. Kinnunen. equipment as described in Spencer et al., 1992).The c-axis (figure 8). The surfaces along the basal pina- photomicrography employed new illumination meth- coids were full of hexagonal etch pits. The pits varied ods and instruments designed by Ihnunen (1991a,b). greatly in area and depth; some had stepped walls. The gem beryls examined ranged in color from PHYSICAL APPEARANCE AND pale yellow to "golden" yellow, pale yellow-green to GEMOLOGICAL PROPERTIES pale green, and pale blue (see, e.g., figure 9).The gemo- The strongly etched crystals showed prism faces that logical properties, as described in table 2, appear to were striated and/or full of individual rectangular pits, be consistent with gem beryls in these color varieties complex groups of pits, or strings of pits along the from other localities (Liddicoat, 1989; Sinlzankas, 1989).Note that the specific gravity is slightly high- er than that given for pure Be3d2Si6Ol8(2.62-2.66)) Figure 8. The surface texture on the prism face of but corresponds well to the values given for aquama- this Luumaki yellow beryl crystal is typical of the material found at this locality. Prolonged natural rine and other pale beryls (2.628-2.730) with a low etching has produced the stepped, mosaic-lilw sur- alkali content (see, e.g., Sinlzanlzas, 1989, p. 191). face features, with etch pits and hillocks. Photomicrograph by IZari A. Kinnunen; transmit- INTERNAL CHARACTERISTICS ted Rheinberg illumination (bl~lelyellowdual- The mineral inclusions identified in the Luuinalzi circular filter to enhance the three-dimensional effect)and shadowing; magnified 8x. beryls-small albite crystals, mica, quartz, beryl (observable only with crossed ), and clay and a hematite-like material filling fractures and growth tubes-are known to occur in beryls from oth- er localities (see, e.g., Giibelin and Koivula, 1986; Sinkanlzas, 1989).However, certain other internal fea- tures appear to be distinctive of this occurrence. Growth tubes and corrosion tubes were common near the basal planes of the crystals examined (figure 10). They were observed to run parallel to the c-axis and usually to widen as they approached the surface of the crystal, similar to the "truinpet-Mze" inclusions described in the pegmatitic beryls from the Ulcraine (Bartoshinslciy et al., 1969; Sinlzankas, 1989, p. 245). In cut stones, however, the terminations may be thin. These inclusions are similar to the growth tubes in aquamarines lznown as "rain" (see Giibelin and Koivula, 1986).In Luuindzi beryls, however, the inclu- sions appeared wider than is typical for "rain," main-

Notes and New Techniques GEMS & GEMOLOGY Spring 1993 ly because of the etchphenomena; some are more properly classified as corrosion tubes. Primary fluid inclusions (three-phase type) were found in negative crystals along former growth zones, in irregular cavities, and in tube-like channels along the c-axis of the gem beryl. Pseudosecondary and sec- ondary fluid inclusions were found in partially healed planes with a random orientation, common- ly as "veils" showing fingerprint-likehealing patterns. Study of the primary and secondary fluid inclu- sions with microscope heating and freezing stages revealed the following characteristics for the Luumalu beryls: phase composition at room temperature- water 52%-76%, vapor 24%-48%) daughter minerals Figure 9. Luumaki gem beryls in a wide range of 2%-3% (one isotropic, two anisotropic, and one non- colors have been faceted. The large oval stone at magnetic opaque); homogenization temperature- the top weighs 41.7 ct and is 27 mm wide. All of these stones are of natural color. Photo by Iari 37O0390"C; salinity-7.3%-7.5% NaCl equivalent; Vaatainen. -0.7; pressure estimate-0.2 tol.0 lzbar (see Kinnunen et al., 1987);and pressure-corrected crys- tallization temperature-400° to 490°C. These char-

TABLE 2. Gemological properties of gem beryl from a pegmatite in LuumM, Finland.a

.I Figure 10. Growih tubes parallel to the c-axis were Color q Transparent "golden" yellow, pale I found to be characteristic of Luumdzi beryl. Small yellow, pale yellow-green, pale syngenetic mineral inclusions (albite) can be seen green, medium green or--rarely- natural (pale blue) aquamarine here in the ends o/ he needles. IJhotomicrograph by I

"Prowies li.sted were obtained frwn seven pieces olrougt+sk ye/bw and one pale gmnd15 faceted stones. With the excqotion of dichroism, the gemological propedes of the heat-treated niaterial were not tested. See texl for methcds used.

Notes and New Techniques GEMS 8: GEMOLOGY Spring 1993 35 Figure 11. Large, nat~zrallydecrepitated fluid inclu- Figure 12. In ths heat-treated yellow beryl from sions, like those shown here, appear to be diagilos- Luumaki, the once fluid-containing cavities are tic of Luumalzi gem beryls The small cracks now empty. They appear dark because of total incorporate submicroscopic fluid inclusions as a reflection of transmitted light. Note, too, the differ- result of healing during recrystallization. ent appearance of the micro-fractures that sur- Photomicrograph by Kari A. Kinnunen; darkfield round the . Photomicrograph by Kari A. illumination, magnified 32x. Kinnunen; magnified 32x. acteristics are typical of late aqueous fluids from et al., 1970; Sinlzanlzas, 1989; Correia-Neves et al., pegmatitic environinents (cf. Koedder, 1984). 1984).The unit-cell dimensions of the various color Many of the large fluid inclusions seen in the varieties did not dlffer markedly from one another. Luuinalu gem beryls were surrounded by networks of micro-fractures (figure 1I), small cracks that formeci HEAT TREATMENT during natural decrepitation. These micro-fractures According to Nassau (1988),the yellow color of beryl healed in recrystallization, at which time small sec- is caused by ferric iron (~e~')that substitutes for alu- ondary fluid inclusions were trapped. A few of the cut stones also showed these inclusions, which have TABLE 3. Chemical composition of Luumaki gem betyiva not been reported in beryls from other localities. men the inclusions were examined with a stereomicro- Yellow Green scope and pinpoint lighting, they closely resembled the Range Average Range Average flower-like discs, or "sun-spangle" inclusions, found Oxidea (wt. %) in treated (see Gubelin and Koivula, 1986). SiO:, 64.3246.09 65.08 Note that the fractures formed during the heat treat- A203 16.5517.44 16.86 inent of beryl are different (air filled) and show no Be0 13.71 healing textures (figure 12). F+03 0.33-0.48 0.41 NqO 0.02-0.06 0.04 CHEMICAL COMPOSITION YO 0.01 MgO 0.00-0.07 0.02 The chemical composition of the Luumdzi gem beryls CaO 0.00-0.02 0.01 (table 3) closely resembles that of certain Uluainian H2O+ 1.02 and Brazilian gem beryls (see, e.g., Bartoshinsluy et Trace element (ppm) al., 1969; Correia-Neves et al., 1984).Both the green Co and "golden" yellow varieties were found to be poor 293 Cs 278 in alkali and allzali metals compared to peg- Zn 69 matite beryl in general (Cerng, 1975), but they con- Sc 49 tained minor concentrations of iron and water. Beryls Cr 18 found in crystal poclzets in pegmatites and granites are Ni 16 typically low in allzalis (Cernq, 1975). V 19 Unit-cell data for the "golden" yellow beryl are as - "SKIa FeD3 (= total iron), rVa@, MgO, and 00were anal@ follows: the P6/mcc, a = 9.203 (1)A and by micrqwobe kchniques lrom a thin sectbn oleach crystd; the aver- c = 9.192 (2)A, vol. = 672.68 A3, c:a = 0.999. The val- age is based on nine deterrnimtions. BBeO, ti@, and Cs were assayed ues agree with those calculated from the chemical lrom a disso/ved beryl sample with atomic absorption spectroscopy (PAS). The olher trace elements were determined from the dissolved data. The lengths of both crystallographic axes are beryl WI?~inductively coupled plasma-atomic emission spectromety close to those of pure Be3Al2Si6Ol8,or of Brazilian and (ICP-AES): H20+ was determined with a Leco RMGl W rap~dmois lure determinator. All 01 the determinations are lrom lhe same two Uluainian beryls that contain minor amounts of water specimens n,d. = not detm'ned. in addition to the major elements (see, e.g., Balzalzin

Notes and New Techniques GEMS & GEMOLOGY Spring 1993 rninum in the structure of the mineral. In green beryl, of gem minerals. To date, however, mining has pro- iron occurs partly in the channel position and partly duced relatively little gem-quality beryl. Because only replaces aluminum. Heat treatment fades the yellow a small portion of the dike is visible on the surface, color and changes green varieties to blue. though, the economic significance of the occurrence Heating experiments with Luumalzi beryl gave is impossible to estimate without further study, fur- similar results. The "golden" yellow beryl faded to ther exposure of the pegmatite, and/or core drilling. nearly colorless if the stones were lzept two to five The complex rapalcivi granite-anorthosite intru- hours in an oven at temperatures between 400" and sions seem to have potential as sources of gem min- 500" C. Green beryl became blue when heated under erals in Fmland. In addition to the laown spectrolite the same conditions. The specific hue and saturation deposits, the authors have found minor poclzets of of the heat-treated blue color varied from one sample gem minerals. The mineralogic and geologic similar- to the next, in direct relationship to the intensity and ities between the Luumalzi pegmatite and the pro- shade of the original green material (see Ehrnrooth ductive Uluainian gem beryl and topaz pegmatites, and Tuovinen, 1989). which occur in a rapalzivi-type granite of the same age (Bartoshinsluy, 1969; Sdzankas, 1989; KosM et al., CONCLUSION 1991), also favor this conclusion. In addition, peg- The Luumalzi pegmatite shows features typical of matite~usually occur in groups or clusters (i.e., peg- miarolitic pegmatites (i.e., those with crystal-lined matite districts), so it is lilzely that there may be more cavities; Cernjr, 199 I), which are important sources gem-bearing pegrnatites in this region of Finland.

REFERENCES Appleman D:E., Evans H.T. (1973)Job 9214: Indexing and least- Kinnunen K.A. (1991b)Parempia valokuvia stereomilrroskoopiUa squares refinement of powder diffraction data. In U.S. (High-qualityphotomicrographs with the stereomicroscope). Geological Survey, Computer Contributio~~20, U.S. National Geologi (publication of the Geological Society of Finland), Technical Information Service, Document PB2-16188,62 pp. Vol. 43, No. 6, pp. 113-1 14. Baltakin V.V., Rylov G.M., Belov N.V. (1970)X-ray diffraction data I(innunen K.A., Lindqvist K., Lahtinen R. (1987)Fluid history from for identification of beryl isomorphs. crystal cavities in rapaluvi, Pyterlahti, southeastern Finland. International, Vol. 7, No. 6, pp. 924-933. Bulletin o/ the Geological Society of Finland, Vol. 59, Part 1, Bartoshinsltiy Z.V., Matltovskiy O.I., Srebrodolskiy B.I. (1969) pp. 3544. Aktsessornyy berill iz kamernykh pegmatitov Ultrainy Koshil LM., Vasilishin I.S., Pavlishin V.L, Panchenko V.I. (1991) (Accessoryberyl froin the chamber pegnatites of the Uluaine). Wolodarsk-Wolynskii Geologischer Aufbau und Mineralogie Mineralogitcheslziy Sbornik, Vol. 23, pp. 382-397. der Pegmatite in Wolynien, Ukraine (Geology of Wolodarsk- Cernjr P. (1975)Alltali variations in pegmatitic beryl and their pet- Wolynslu; and the mineralogy of the pegma tites in Wolhynia, rogenetic implications. Neues Iahrbuch fiir Mineralogie, Ukraine]. Lapis, Vol. 10, No. 10, pp. 2740. Abhandlungen, Vol. 123, No. 1, pp. 198-212. Lahti S.1. (1981) On the granitic pegrnatites of the Erajarvi area in Cerny P. (1991)Rare element granitic pegmatites. Part 1: Anatomy Orivesi, southern Finland. Geological Survey of Finland and internal evolution of pegmatite deposits. Geoscience Bulletin, Vol. 314, 82 pp. (monograph). , Vol. 18, No. 2, pp. 49-67. Lahti S.I., Sailtkonen R. (1986)Kuiuite from the Haapaluoma peg- Correia-Neves J.M., Monteiro R.L.B.B., Dutra C.V. (1984) matite quany, western Finland. Bulletin of he Geological Composi~Hoquimica de berilos pegnatiticos do Brasil e seu Society of Finland, Vol. 58, No. 2, pp. 47-52. sigruficado petroldgico e metalogenetico (Chemical compo- Liddicoat R.T. Jr. (1989)Handbook of Gem Idenlification, 12th sition of pegmatitic beryls in and their petrological sig- ed. Gemological Institute of America, Smta Monica, CA. nhcance). Revisla Brasileirn de Gwciencas, Vol. 14, No. 3, pp. Nassau K. (1988) Enhancement. Butterworths, London. 137-146. Pitkiinen R. (1991) Luu~naenjalokivipegmatiitti (The Luumaki Ehrnrooth E.-K., Tuovinen P. (1989) Luumlen beryllien lain- gem beryl pegmatite). Kivi (publication of the Finnish Gem pokasittely (Heat treatment of the Luumalti beryls). Hobbyists' Society), Vol. 9, No. 1, pp. 27-29. Gemmologian fiosaralta (publication of the Gemmological Read P.G. (1991) Gemmology. Butterworth-Heinernann, Oxford. Society of Finland), No. 18, pp. 4-19. Roedder E. (1984) Fluid inclusions. In P.H. Ribbe, Ed., Reviews in Erhetsi O., Nieminen K., Niinistij L. (1973)Two transparent beryl Mineralogy, Vol. 12, Mineralogical Society of America, varieties from the Kaatiala pegmatite, Finland. Bulletin of the Washington, DC, 644 pp. Geological Society of Finlnnd, Vol. 45, Part 2, pp. 125-130. Sinkanltas J. (1989) and Other Beryls. Geoscience Press, Giibelin E.J., Koivula J.I. (1986)Photoallas of Inclusions in Prescott, AZ. . AUC Edition, Ziirich, 532 pp. Spencer R.J., Levinson A.A., Koivula J.I. (1992)Opal from Quektaro, Haapala 1. (1966) On the granitic pegmatites of the Peraseinajoki- Mexico: study. Gems d Gemology, Vol. 28, Alavus area, South Pohjanmaa, Finland. Bullelin de la No. 1, pp. 2834. Comniission Gdologique de In Finlnnde, Vol. 224, 98 pp. Vaasjoki M. (1977)Rapaluvi granites and other postorogenic rocks Kinllunen K.A. (1991a)Three-dunensiond nlicroscope image using in Finland: Their age and the isotopic composition of anaglyphic filters: A new aid to fluid inclusion . certain associated mineralizations. Geological Survey American Mineralogist, Vol. 76, pp. 657458. of Finland Bulletin, Vol. 294,64 pp. (monograph].

Notes and New Techques GEMS 8: GEMOLOGY Spring 1993 37