Jasper
Image: Darla Sondrol (CC0)
Mineral NameJasper
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemcubic
Lustervitreous
Streak ColorWhite
CleavageNone
FractureConchoidal
Specific Gravity2.65
Colorsred, brown, yellow, green, blue, black, multicolored
TransparencyOpaque
Type LocalityWidespread
Mineral GroupSilicates
Usesjewelry, ornamental stone, decorative objects, lapidary material
Associated Mineralsquartz, hematite
Raritycommon
Description
A microcrystalline variety of quartz, typically opaque and often exhibiting vibrant red, brown, or yellow colors due to iron inclusions, as seen in the reddish-brown specimen in the image.
Geological Context
Forms in various geological settings, including sedimentary deposits, volcanic rocks, and hydrothermal veins, often as a result of silica precipitation and replacement of other minerals.
