Dyrnaesite-(La) is a rare-earth phosphate mineral with the formula Na
8Ce4+
(La,REE)
2(PO
4)
6. Dyrnaesite-(La) is related to vitusite-(Ce), another rare-earth phosphate mineral.[2][3] It comes from lujavrite, a type of alkaline syenite rock, of South Greenland. Dyrnaesite-(La) is one of few known minerals with essential tetravalent cerium, the other two being cerianite-(Ce) and stetindite.[4][5]
Dyrnaesite-(La) | |
---|---|
General | |
Category | Phosphate mineral |
Formula (repeating unit) | Na 8Ce4+ (La,REE) 2(PO 4) 6 |
IMA symbol | Dyr-La[1] |
Crystal system | Orthorhombic |
Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
Space group | Pnma |
Unit cell | a = 18.466, b = 16.011 c = 7.027 [Å] (approximated) Z = 4 |
Identification | |
References | [2][3] |