Carnelian

Carnelian
Dutch: Carneool.
Names: Chalcedony variety; Silica; Silicon dioxide.
Chemical: SiO2.
Formula mass: 60 g/mol
Color: red, orange, reddish.
Hardness: 6.5 to 7.0.
Crystal system: Trigonal.

Mineralogy
Chalcedony variety.