Oxide minerals and their features

The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys 

Hematite

Chemical formula : Fe2O3 

Mohs Scale : 5.5 - 6.5

Crystal System : Trigonal

Melting Point : 1538 C

Diaspore

Chemical formula :  AlO(OH) 

Mohs Scale : 6.5 - 7

Crystal System : Orthorhombic

Goethite

Chemical formula :  FeO(OH) 

Mohs Scale : 5, 5.5

Crystal System : Orthorhombic

Wulfenite

Chemical formula : PbMoO4 

Mohs Scale : 3

Crystal System : Tetragonal

From Mexico

Psilomelane

Chemical formula : (Ba,H2O)2Mn5O10 

Mohs Scale : 5-6

Crystal System : Monoclinic

Hematite