General Information:
Chemical Formula:
(Mg,Fe++)3Si4O10(OH)2(Ca,Na)0.2-0.3(Mg,Fe++)3(Si,Al)4O10(OH)2·4(H2O)
Environment:
Low temperature environments in ancient lake sediments. Also found in low-grade Mg-rich metamorphic rocks.
IMA Status:
Approved IMA
Locality:
TL: Italy, Monte Chiaro, Taro valley. Amargosa desert region, Death Valley, California, USA.
Name Origin:
Named for Andrea Alietti (1923-), clay mineralogist.
Physical Properties:
Cleavage:
[???] Perfect
Color:
white, dark green, or buff.
Habits:
Microscopic Crystals - Crystals visible only with microscopes., Platy - Sheet forms (e.g. micas).,
Hardness:
1-2 - Between Talc and Gypsum
Luster:
Earthy (Dull)
Streak:
white
More details...