Vajdakite

Formula: (MoO₂)₂As₂O₅·3H₂O

Origin of name: Named for Josef Vajdak (1930-), for his significant contribution in the study of minerals in the Jachymov ore district.

Crystal system: Monoclinic

Crystal class: 2/m

Twinning: 

Unit cell: a = 7.0515, b = 12.0908, c = 12.219, β = 101.268°

Colour: Green, greenish gray

Diaphaneity: Translucent

Luster: Vitreous

Habit: Acicular, aggregates

Hardness: 

Specific gravity: 3.5

Cleavage: [100] perfect, [010] good

Tenacity: 

Streak: Light grayish green

Synonyms/varieties:

Comments: