Sinkankasite

Formula: MnAl(PO₃OH)₂OH.6H₂O

Origin of name: for John Sinkankas, American mineral collector and author

Crystal system: triclinic

Crystal class: -1

Twinning: common on {100} repeated, polysynthetic

Unit cell: a = 9.58 Å, b = 9.79 Å, c = 6.88 Å, a = 108.1°, b = 99.6°, g = 98.7°

Colour: colourless to white

Diaphaneity: 

Luster: vitreous to dull

Habit: crystals elongated, smaller than 3 mm, polysynthetic twinning

Hardness: 4

Specific gravity: 2.27

Cleavage: 1; { 100} good

Tenacity: 

Streak: 

Synonyms/varieties:

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