triclinic Tectosilicates
Andesine (Tabular)
(Ca,Na)(Al,Si)4O8
Quick Facts
Hardness
6.0
Specific Gravity
2.65
Refractive Index
1.543
Optical Character
Biaxial -
Crystal Structure
#! Species: Andesine
#! System: Triclinic (-1)
#! Habit: Tabular on {010}
triclinic[-1]:{010}@1.0 + {001}@0.8 + {110}@0.6
triclinic
-1
{010} {010} {001} {110}
Physical Properties
Crystal Systemtriclinic
Hardness (Mohs)6.0
Specific Gravity2.65
CleavagePerfect {001} and good {010}
FractureUneven to conchoidal
LustreVitreous
Optical Properties
Refractive Index1.543
Birefringence0.008
Optical CharacterBiaxial -
Colours
RedOrange-redGreenYellow-green
Localities
Tibet (China)MongoliaOregon (USA)Democratic Republic of Congo
Common Inclusions
Twin lamellaeSchiller inclusions
Known Treatments
Copper diffusion (controversial, for red colour)
Crystal Forms
pinacoidprism
Notes
Red andesine origin and treatment status frequently debated in gem trade
Interactive Preview
Open this crystal in the CDL Playground to rotate, export, and explore in 3D.
Open in Playground #! Species: Andesine
#! System: Triclinic (-1)
#! Habit: Tabular on {010}
triclinic[-1]:{010}@1.0 + {001}@0.8 + {110}@0.6
Related Minerals
Other minerals in the triclinic system
