Thomasclarkite-(Y)
(repeating unit)(Na, Ce)(Y, REE)(HCO3)(OH)3·4(H2O) IMA symbol Tcl-Y[1] Crystal system Monoclinic Crystal class Sphenoidal (2)
(same H-M symbol) Space group P2 Identification Formula mass 375.77 g/mol Color White, yellow Crystal habit Blocky crystals, pseudo-tetragonal Twinning Common on (101) Cleavage [010] Perfect, [101] parting Fracture Uneven Tenacity Very brittle Mohs scale hardness 2–3 Luster Vitreous (glassy) Streak White Diaphaneity Translucent to transparent Specific gravity 2.30 Optical properties Pseudouniaxial negative 2V (meas.) ≤ 5° Refractive index nα = 1.40, nβ = 1.540, nγ = 1.540 Birefringence δ = 0.140 Other characteristics Radioactive 770 Bq/g References [2][3][4]
(same H-M symbol)
Thomasclarkite-(Y) is a rare mineral which was known as UK-93 until 1997, when it was renamed in honour of Thomas H. Clark (1893–1996), McGill University professor. The mineral is one of many rare-earth element minerals from Mont Saint-Hilaire. The only reported occurrence is in an alkalic pegmatite dike in an intrusive gabbro-nepheline syenite.
See also
References
- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ http://rruff.geo.arizona.edu/doclib/hom/thomasclarkitey.pdf Handbook of Mineralogy
- ^ http://webmineral.com/data/Thomasclarkite-(Y).shtml Webmineral data
- ^ http://www.mindat.org/min-7336.html Mindat
- Mont Saint-Hilaire
- v
- t
- e