Ancylite is a group of hydrous strontium carbonate minerals containing cerium, lanthanum and minor amounts of other rare-earth elements. The chemical formula is Sr(Ce,La)(CO3)2(OH)·H2O with ancylite-Ce enriched in cerium and ancylite-La in lanthanum.[2][3]
| Ancylite | |
|---|---|
 Nenadkevichite with ancylite crystals on the side | |
| General | |
| Category | Carbonate mineral |
| Formula (repeating unit) | Sr(Ce,La)(CO3)2(OH)·H2O |
| IMA symbol | Anc[1] |
| Strunz classification | 5.DC.05 |
| Dana classification | 16b.1.1.1 |
| Crystal system | Orthorhombic |
| Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
| Space group | Pmcn |
| Identification | |
| Color | Light yellow, orange-yellow, yellow-brown, grey |
| Cleavage | None |
| Fracture | Splintery |
| Tenacity | Brittle |
| Mohs scale hardness | 4–4.5 |
| Luster | Dull |
| Streak | White |
| Diaphaneity | Translucent |
| Density | 3.95 g/cm3 |
Ancylite was first described in 1899 for an occurrence in the Narsarsuk pegmatite in west Greenland and named from the Ancient Greek: αυκιλος for curved in reference to its rounded or distorted crystal form.[2][4]
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.
- ^ a b http://webmineral.com/data/Ancylite-(Ce).shtml Webmineral data Ancylite-Ce.
- ^ http://www.handbookofmineralogy.org/pdfs/ancylitela.pdf[permanent dead link] Handbook of Mineralogy.
- ^ http://www.mindat.org/min-216.html Mindat.