Oxides
Browse gemstones by their mineral families and classifications. From quartz to corundum, explore the rich diversity of natural crystal structures, compositions, and geological origins that define each gem type.

Cassiterite
Hardness: 6
BlackBrownYellowRed

Corundum
Hardness: 9
RedBlueYellowGreenColorlessPinkOrangePurpleBrownBlack

Hematite
Hardness: 5.5
BlackSilver-grayMetallic grayRedBrown

Ilmenite
Hardness: 5.5
BlackDark GrayBrown

Magnetite
Hardness: 6
BlackGrayBrown

Rutile
Hardness: 6
RedBrownYellowGoldBlack

Spinel
Hardness: 7.5
RedPinkBlueGreenBlackPurpleYellowOrangeBrown

Zincite
Hardness: 4
YellowRedOrangeBrownBlack