Thomasclarkite-(Y)
Appearance
Thomasclarkite-(Y) | |
---|---|
General | |
Category | Carbonate mineral |
Formula (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] |
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
[edit]References
[edit]- ^ 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