Katoite

Formula:  Ca₃Al₂(SiO₄)_3-x(OH)_4x   x = 1.5 - 3

Origin of name:  For Akira Kato, Japanese mineralogist

Crystal system:  Cubic

Crystal class:  4/m -3 2/m

Twinning: 

Unit cell: 

Colour:  Milky white

Diaphaneity: 

Luster: 

Habit:  Crystals rounded, tiny, rarely octahedral, to 0.1-0.3mm

Hardness: 

Specific gravity:  2.76

Cleavage:  None

Tenacity: 

Streak: 

Synonyms/varieties:

Comments:  Series with grossular and hibschite