Mineral Group · 20 minerals
Oxide & Hydroxide Minerals
Minerals
20
Hardness
3.5-9 Mohs
Crystal Systems
Trigonal, Orthorhombic, Cubic +2 more
What Defines the Oxides Group
Metal-oxygen compounds ranging from the hardest natural substances (corundum, Mohs 9) to common iron ores (hematite, magnetite). Includes ruby and sapphire (both corundum), spinel, rutile, and chrysoberyl. This group contains some of the most economically important and gemologically prized minerals.
Minerals in This Group
Alexandrite
The Chameleon Gem
Cassiterite
The Tin Stone
Cat's Eye Chrysoberyl
The Winking Stone
Chrysoberyl
The Cat's Eye Gem
Coltan
The Digital Age Mineral
Cuprite
The Ruby Copper
Diaspore
The Color-Change Gem
Goethite
The Poet's Iron
Hematite
The Blood Stone
Magnetite
The Lodestone
Padparadscha
The Lotus-Blossom Sapphire
Pink Sapphire
Chromium's Softer Signature
Ruby
The King of Gems
Rutile
The Titanium Needle
Sapphire
The Gem of the Heavens
Spinel
The Great Impostor
Star Ruby
The Asterism Corundum
Star Sapphire
The Celestial Star Stone
Yellow Sapphire
Pukhraj, the Stone of Jupiter
Zincite
The Neon Zinc Crystal