Andradite
Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
Mineral NameAndradite
Chemical FormulaCa3Fe2(SiO4)3
Mohs Hardness6.5
Crystal Systemcubic
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal to uneven
Specific Gravity3.85
Colorsbrownish-green, olive-green, brown
Transparencytranslucent
Type LocalityStanley Butte area, Stanley Butte, Stanley District, Santa Teresa Mts, San Carlos Indian Reservation, Graham County, Arizona, USA
Mineral GroupSilicates (Garnet Group)
Usescollector, abrasive, gemstone
Associated Mineralscalcite, epidote, diopside, magnetite
Rarityuncommon
Description
This specimen displays a dense aggregation of numerous brownish-green to olive-green andradite crystals, exhibiting well-formed dodecahedral or trapezohedral habits with a distinct vitreous luster.
Geological Context
Andradite typically forms in contact metamorphic rocks, especially skarns, where iron-rich fluids interact with carbonate rocks, or in certain igneous environments.
