Saponite - (Ca,Na)0.3(Mg,Fe 2+)3(Si,Al)4O10(OH)2ˇ4H2O

Phyllosilicates

Habit: White, yellow, gray, blue, green, reddish or brown. Crystals minute, pseudo-hexagonal and tabular; bladed, fibrous, flaky or subparallel aggregates; also nodular, fine-grained or massive. Greasy luster; translucent. White streak.


Environment: Hydrothermally deposited in mineralized veins and in vesicles in basalt and formed in fissures cutting calc­silicates, iron-rich skarns, amphibolites and serpentinites.


Etymology: From the Latin sapo, meaning "soap," which saponite resembles.