Banalsite

Formula:  BaNa₂Al₄Si₄O₁₆

Origin of name:  From combination of symbols for elements

Crystal system:  Orthorhombic

Crystal class:  2/m 2/m 2/m

Twinning:

Unit cell: a =  8.496 Å, b = 9.983 Å, c = 16.755 Å

Colour:  White

Diaphaneity: translucent

Luster:  Vitreous, pearly on cleavage

Habit:  Massive

Hardness:  6

Specific gravity:  3.065

Cleavage:  2; {110}and {001} distinct

Tenacity:

Streak: White

Synonyms/varieties:

Comments: Feldspar group. Found in veinlets through manganese ore and in lenses in metamorphosed mudstone