Bityite was encountered in thee lithium pegmatite dykes in the Eräjärvi area in Orivesi, southern Finland. The mineral is closely associated with beryl occurring in pseudomorphs after it or in cavities with bertrandite, fluorite and fluorapatite as a fine-scaled white or yellowish mass with a pearly lustre. This is the first description of the mineral from Finland. A bityite sample found in a small abandoned feldspar quarry called Maantienvarsi was studied in detail. Wet chemical analysis shows (wt °/o): Si0 2 33.35, AljO, 34.61, Fe 2 Oj tot. 1.37, MgO 1.84, CaO 14.07, BeO 7.21, Na z O 0.10, K 2 0 0.16, Li 2 0 2.32, H 2 0+ 5.33 and F 0.39. The formula computed on the basis of 24 anions is as follows (Z = 2): CaK^KoojNaoo^Li, l9 Al3. 6g Mg 0 3 5 Fe 0. 13)(Al l 53Be 2. 21 Si 4. 26)Oi 9 .3o(OH) 4 , 4 Fo. 16. The mica is monoclinic and the space group is C2/c or Cc with a = 4.99 Å, b = 8.68 Å, c= 19.04 Ä and (3 = 95.17°. The refractive indices are c* = 1.650, ß= 1.658, 7= 1.660 and-2Vcalc. = 52.9°. The specific gravity is near 3.05 and the density is 3.12 g/cm 3. The following infrared absorbtion bands were recorded for the mineral (cm-1): 3620, 3451, 1634, 1400, 949, 707, 537 and 431. The lack of absorbtion near 800 cm-1 caused by Al-O-AI stretching vibrations indicates ordering of tetrahedral Si and Al + Be. The analytical data collected from the literature show a series between trioctahedral bityite Ca 2 (Li 2 Al 4)(Al 2 Be 2 Si 4)O 20 (OH) 4 and octahedral mica margarite Ca 2 Al 4 (Si 4 Al 4)O 20 (OH) 4. Natural Li-Be brittle micas are always deficient in Li, and there seems to be a miscibility gap between the end members. In contrast to the ideal formula, at most 1-1.2 of the two possible Li atom sites are filled. The valency balance is achieved by substituting AP + for Li 1+ + Be 2+ and O 2for (OH + F) 1-. The replacement of cations may be more complex. The Maantienvarsi Li-Be mica is typical bityite with the high content of Li and Be and its properties agree well with those of similar micas. The sum of octahedral cations, 5.35, is the highest known of the Li-Be micas reported in the literature.
RISTO, 1983: Kivesvaara C2 chondrite: silicate petrography and chemical composition. Bull. Geol. Soc. Finland 55, Fragments of the Kivesvaara meteorite were said to have been found in Paltamo, northern Finland in 1968. The chemical and mineral composition and the textural features show that this meteorite is a rare C2 carbonaceous chondrite. The research material consists of two fragments with traces of fusion crust (total weight 164 g). The meteorite is composed of a fine-grained phyllosilicate matrix (77.5 vol.%) and of clasts: amoeboid olivine aggregates and finegrained Ca-Al-Ti-rich aggregates (CAI inclusions), fluid drop chondrules and polymineralic fragments, monomineralic grains and fragments mainly of olivine, and opaque minerals. The clasts define a weak planar orientation and most of them are surrounded by black matrix rinds. The chemical composition of the Kivesvaara meteorite closely resembles Murchison C2 chondrite.
IRJA A., 1990: Determination of total and non-carbonate carbon in rock samples by a method using infrared absorption. Bull. Geo!. Soc. Finland 62, Part 2,[149][150][151][152][153][154][155][156] Total and non-carbonate carbon were determined by a method using infrared absorption in 20 international geological reference samples, 13 in-house reference samples and 13 other rock samples. For the determination of total carbon, C TOT , the samples were combusted at 1370°C in oxygen flow. Non-carbonate carbon, C NONC , was determined in a similar way but the samples were leached with hydrochloric acid to remove carbonate carbon before combusting. The concentration of carbonate carbon, C0 2 , was calculated from the difference C T0T -C NON c-The results (C T0T , C NONC and calculated C0 2 ) for the 20 international geological reference samples compared well with published data. The results (C XOT , C NONC and calculated C0 2 ) for the 13 in-house reference and 13 other rock samples agreed well with the results obtained by gravimetric methods. The precision of the used method was good: relative standard deviation was about 1%, 5% and 10% when the carbon content of the sample was 10%, 1% and 0.1% respectively. The effective detection limit was 0.01 -0.02% C.
A purple transparent crystal of spodumene, or kunzite, was encountered in the Haapaluoma feldspar quarry, western Finland. The crystal, which is about seven centimetres long, is embedded in purple, fine-scaled lepidolite. The kunzite has crystallized in a postmagmatic fracture filling of albite-quartz-spodumene-lepidolite-red tourmaline crossing the main pegmatite dyke. Spodumene is a common mineral in certain pegmatites, but this is the first report of kunzite, a gem quality spodumene, in Finland. The wet chemical analysis of the Haapaluoma kunzite shows (wt%): Si0 2 63.85, TiOj 0.01, A12Oj 27.72, MnO 0.16, Fe203 tot. 0.16, MgO 0.05, ZnO 0.01, T120 0.0, CaO 0.07, BeO 0.00, Na 2 0 0.59, K 2 0 0.13, Li 2 0 7.49, Rb z O 0.00, Cs 2 0 0.00, P 2 0, 0.00, H 2 0 + 0.08, H 2 0-0.02, total 100.34. The trace elements determined with an optical emission spectrograph are as follows (ppm): Cr 510, Ga330, Sn 120, Sc 26, Ge 19, Sr <30, Co <20, Cu <15, Ni <15 and V <15. The unit cell formula computed on the basis of six oxygens (Z = 4) is as follows: Li^Na^Al, ^Si,"O^ The mineral is strongly pleochroic with X = Y = amethystine purple and Z = weak purplish or colourless. The optical properties are a = 1.660, ß = 1.665, 7 = 1.679, +2Vmeas. = 61° and +2Vcalc. = 62°. The mineral shows weak pale orange fluorescence under long and short wave UV light. The measured specific gravity (3.19) is identical to the calculated density within the limits of measuring accuracy. The unit cell is monoclinic with the space group C2/c and a = 9.469 A, b = 8.399 Å, c = 5.225 Å, ß = 110.16° and V = 390.04 Å 3. The composition of kunzite and a grey spodumene from the Na-stage assemblage of the same quarry are nearly identical. The content of iron and lithium is, however, lower in kunzite and the content of sodium is higher. The colour of the mineral may be due to the presence of relatively high concentrations of Mn 3+ and a low Fe/Mn ratio (1.0). The chemical composition and physical properties of the Haapaluoma kunzite resembles closely to those reported in the literature for similar spodumene varieties.
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