SiO2Trigonal
Agate
SiO2
SilicatesChemical FormulaSiO2
Crystal SystemTrigonal
Mohs Hardness7
Specific Gravity2.6
ColorMulticolored, banded
LusterVitreous to waxy
StreakWhite
CleavageNone
FractureConchoidal
Occurrence
Banded variety of chalcedony. Found in volcanic rocks. Each band represents a growth period.