write a short note on the features of minerals
Answers
Answer:
Magnetism
colour
Streak
Hardness
Tenacity
Explanation:
Colour:--Minerals have specific colouration in pure state. A mineral called calcite is white in colour, feldspar is whitish pink whereas gypsum is yellowish in colour. Minerals give colour to the rocks. Although their colours change due to various impurities present, nevertheless the colour of a rock can give a clue about the minerals it contains.
Luster:
Luster is a property which gives a mineral its characteristic appearance. It depends on whether light is absorbed, refracted of reflected by the mineral. Metallic, glassy, luminous and dull are different kinds of luster.
Hardness:
Talc is the softest mineral and diamond is the hardest. German scientist Friedrich Mohs, devised a scale of hardness which is varied from 1 to 10. A mineral can scratch another mineral softer than it. Table 5.3 shows minerals placed according to their increasing order of hardness.
Shape:
Crystals have regular arrangement of atoms and molecules. Most minerals are crystalline but as these crystals rub against each other their shapes change. When melted lava pours out from the mouth of a volcano it may flow down the mountainside and harden into a rock that does not contain a crystal.