Tungusite

Formula: Ca₁₄Fe₉Si₂₄O₆₀(OH)₂₂

Origin of name: after locality Tunguska River, Siberia, Russia

Crystal system: triclinic

Crystal class: -1

Twinning:

Unit cell: 

Colour: grass-green to yellowish green

Diaphaneity: 

Luster: pearly (weakly)

Habit: plates to 0.5 cm, radiating-fibrous crusts

Hardness: about 2

Specific gravity: 2.59

Cleavage: none

Tenacity: 

Streak: 

Synonyms/varieties:

Comments: series with gyrolite