Major Mineral Groups (Part 7)
Oxides
• Oxide minerals are made up of oxygen and one or more metals.
• Common oxide minerals include: hematite and limonite
Hematite Pronounce:
• Hematite, an iron oxide, has a composition of Fe2O3.
• Hematite is identified by its non-metallic or metallic luster and its red to red-brown streak.
• Hematite is identified by its non-metallic or metallic luster and its red to red-brown streak.
• Its hardness is 1.5 to 5.5.
• Its specific gravity is 4.9 to 5.3.
• Hematite is used in pigments and as an iron ore.
Hematite, shown here, is an iron oxide. It is a common iron ore. (Photographs by Parvinder Sethi)
• Limonite, another iron oxide, has a composition of Fe2O3·nH2O.
• Limonite is identified by its non-metallic luster; dull earthy yellow to dark brown color; and its yellow to brown streak
• Its hardness is 1.5 to 5.5.
• Its specific gravity is 3.6 to 4.0.
• Limonite is used in pigments and as an iron ore.
Limonite, shown here, is another iron oxide. It is used in yellow and red pigments. The streak plate beside the sample shows the yellow streak. (Photograph by Parvinder Sethi)