Chlorite
Image: Robert M. Lavinsky (CC BY-SA 3.0)
Mineral NameChlorite
Chemical Formula(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Mohs Hardness2.5
Crystal Systemmonoclinic
Lusterpearly
Streak Colorwhite to pale green
Cleavageperfect basal (one direction)
Fractureuneven
Specific Gravity2.8
Colorsgreen, dark green, yellowish-green, brownish-green
Transparencytranslucent to opaque
Type LocalityHot Springs, Garland County, Arkansas
Mineral GroupSilicates (Phyllosilicates)
Usesindustrial (filler, insulation), collector
Associated Mineralsquartz
Raritycommon
Description
This specimen features dark green, platy crystals of chlorite, often appearing as coatings or inclusions within other minerals. The chlorite is prominently associated with clear quartz crystals.
Geological Context
Chlorite is a common mineral formed during low-grade regional metamorphism of mafic igneous rocks and shales. It also frequently occurs as a hydrothermal alteration product in various igneous and metamorphic rocks.
