 |
MSH News |
|
Table of Contents - Mike Skebo - Bill Plavac - Extracts from several mineralogical sources - Kamen Bogdanov - Malcolm Back, Bob Gault and Bob Ramik - Andy McDonald and Malcolm Back - Liz Fodi Mont Saint-Hilaire Confirmed Species, April 20, 2000 - Malcolm Back, Bob Gault and Bob Ramik (*) denotes type locality Additions since last Official MSH Species list: almandine biotite series caresite* chabazite-Ca chabazite-Na chalconatronite charmarite* edenite ekanite faujasite-Na gmelinite-Na hibschite khomyakovite* manganokhomyakovite* oneillite* orthoclase phillipsite-K phillipsite-Na quintinite* schorl thomasclarkite-(Y)* thorbastnasite Deletions since last Official MSH Species list: edenitic-hornblende herschelite hornblende hydroandradite hydrogrossular hypersthene tetranatrolite Changes since last Official MSH Species list: tadzhikite-(Ce) should read tadzhikite taeniolite should read tainiolite
 Data for MSH unknowns - Andy McDonald, (UK-105) by Malcolm Back UK-69 Ideal Formula: (Na,Ca)15Sr12(Zr,Nb)14Si42B6O144 ˇ 12H2O Symmetry: Trigonal, space group P31c; a = 19.720(1) c = 9.9788(5) Description: As stubby, euhedral hexagonal prisms [{100} and {001}] up to 1.5mm in length that are pale green (possibly owing to inclusions) to colourless, with distinctive green to black rims edging {001}. Occurrence: In a breccia associated with donnayite-(Y) (green in colour), an amphibole group mineral, albite, pyrrhotite, pyrite, biotite, analcime, amphibole, calcite and a burbankite-group mineral (white, fibrous; species undetermined). UK-105 Ideal Formula: unknown, but it is probably a hydrated yttrium phosphate related to xenotime-(Y) Symmetry: unknown Description: Grey to white balls to 3mm diameter with an irregular surface, and an earthy lustre. Broken balls show a radiating structure with a pearly lustre, and is comprised of platy, micaceous crystals. The balls are sometimes covered with a white powder. Only 2 specimens are known at this time although others are probably in collections. M. Back at the ROM is interested in seeing other samples if they are found. Occurrence: These samples were collected in 1988 by Cynthia Peat. They were found in the southeast corner of the quarry in the same area as the sérandite-leifite pipe of that time. Associated minerals include albite in the form of heart-shaped twins (see R.P. Richards, 1989, Rochester Symposium Abstract, page 15) and as larger plates, aegerine and sérandite. UK-107 Ideal Formula: (Na,Ca)6(Zr,Y)3Y3(PO4)(CO3)(OH,F)2 ˇ 2H2O Symmetry: Orthorhombic, space group P222; a = 10.9954(9), b = 10.9946(9), c = 10.9979(9) Description: As thin, pale pink to colourless transparent rims on UK 108. Both occur in sub- to euhedral pseudo-cubes averaging 0.2mm across (in some cases, samples have been found in which the UK 108 has been completely etched away, leaving hollow crystals consisting only of UK 107 rims). Occurrence: In a hydrothermally altered pegmatite associated with donnayite-(Y), sabinaite, cryolite, elpidite, rhodochrosite, horváthite-(Y), analcime, synchysite-(Ce), catapleiite and various zeolites. UK-108 Ideal Formula: (Na,Ca)6Y6(PO4)(CO3)F2 ˇ 2H2O Symmetry: space group unknown; presumably symmetry is lower than cubic. Description: As yellow, translucent to opaque cores surrounded by thin, pale pink to colourless transparent rims of UK 107. Both occur in sub- to euhedral pseudo-cubes averaging 0.2mm across. Occurrence: In a hydrothermally altered pegmatite associated with donnayite-(Y), sabinaite, cryolite, elpidite, rhodochrosite, horváthite-(Y), analcime, synchysite-(Ce), catapleiite and various zeolites. UK-109 Ideal Formula: Na3Ba2Ce(CO3)6 ˇ 3H2O Symmetry: Triclinic, space group Pbar1 (by analogy with weloganite) Description: As black to dark blues rosettes or dish-shaped aggregates (up to 0.7mm across, averaging 0.3-0.4mm) composed of subhedral pseudo-hexagonal plates. Occurrence: In a pegmatite in sodalite syenite (eighth level of the quarry) containing lozenge-shaped magnetite grains surrounded by rims of biotite, etched aggregates of quartz, fluorite (purple), zircon (bright yellow, with {100} dominant), pyrochlore, a burbankite-group mineral [possibly remondite-(Ce)], a Na-dominant polymorph of lemoynite and sphalerite. UK-110 Ideal Formula: Na2ZrSi4O11 ˇ 2H2O Symmetry: Monoclinic, space group P21/a Description: As colourless to pale orange-pink, euhedral platy to tabular crystals arranged in a rosette approximately 3mm across. Individual crystals average 0.8mm across and are flattened on {010}. Occurrence: In a pegmatite (eighth level of the quarry) associated with etched quartz, elpidite (with prominent pinacoidal terminations) and gaidonnayite.
Created by M & H Systems |
