 |
| Psilomelane
Psilomelane is a
hydrous oxide of manganese containing varying amounts of barium, potassium and sodium oxides.
It is steel grey to black in colour and its streak is black. Its hardness ranges from 5 to 7.
Its specific gravity varies from 3.3 to 4.7 and its lustre is sub-metallic or dull.
Psilomelane is used as an ore of
manganese. In India, it occurs in Andhra Pradesh and Madhya Pradesh. |
 |
| 
|
Hematite
Hematite, also known as red iron ore. It
is the most important ore of iron. It contains about 70% iron. It is steel grey or black in
colour. Its streak is cherry red in colour. Its hardness varies from 5.5 to 6.5 and the
specific gravity ranges from 4.9 to 5.3.
India is rich in hematite deposits. One of the world's largest deposit is
situated Bihar State. In Tamilnadu, the iron ores are found in Salem district.
|
|
Magnetite
Magnetite, also
known as magnetic iron ore and is an important ore of iron. It contains about 72% of iron. Its
colour and streak are black. Its hardness ranges from 5.5 to 6.5 and the specific gravity is
5.1. In Tamilnadu magnetic deposits occur in Salem and Tiruchirapalli districts. |
|
|
|
|
Next Gallery
Mineralogy