Celadonite
Celadonite | |
---|---|
General | |
Category | Micas Phyllosilicate |
Formula (repeating unit) | K(Mg,Fe2+ )(Fe3+ ,Al)[Si 4O 10](OH) 2 |
IMA symbol | Cel[1] |
Crystal system | Monoclinic |
Crystal class | Spheroidal (2) (same H-M symbol) |
Space group | C2 |
Identification | |
Color | Blue-green to olive to applegreen |
Cleavage | perfect on {001} |
Tenacity | Fragile |
Mohs scale hardness | 2 |
Luster | Waxy, dull, earthy |
Diaphaneity | Translucent |
Specific gravity | 2.95 - 3.05 |
Density | 2.95 - 3.05 |
Optical properties | Biaxial (-) |
Pleochroism | Visible |
2V angle | 5°- 8° |
Common impurities | Mn, Na, Ca |
Other characteristics | Radioactive 9.11% (K) |
References | [2][3][4] |
Celadonite is a mica group mineral, a phyllosilicate of potassium, iron in both oxidation states, aluminium and hydroxide with formula K(Mg,Fe2+
)(Fe3+
,Al)[Si
4O
10](OH)
2.
It crystallizes in the monoclinic system and usually forms massive aggregates of prismatic crystallites or in dull clay masses. It is soft with a Mohs hardness of 2 and a specific gravity of 3. Typically occurs as dull gray-green to bluish green masses. It forms vesicle fillings and linings in altered basaltic lavas.
It was first described in 1847 on Monte Baldo, near Verona, Italy. The name is from the French celadon, for sea-green. It is one of two minerals, along with glauconite, used in making the pigment known as green earth.
Common impurities are manganese, calcium and sodium (previously known as natrium).
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.
- ^ Mineralienatlas
- ^ Mindat w/ localities
- ^ Webmineral
Wikimedia Commons has media related to Celadonite. |
- Potassium minerals
- Iron(II,III) minerals
- Magnesium minerals
- Aluminium minerals
- Mica group
- Monoclinic minerals
- Minerals in space group 5
- Silicate mineral stubs