DIFFERENCES BETWEEN A ROCK AND A MINERAL

There are some facts one may think he knows in Geology but…oops! They are really obfuscating. The look so elementary that they are easily jettisoned.

A Rock is an aggregate of naturally occurring minerals.

A Mineral is an inorganic, crystalline and naturally occurring substance with a definite chemical composition.

Physical Properties of Minerals

Hardness (measured in Mohs Hardness Scale). It increases downwards.

Talc (softest)

Gypsum

Calcite

Fluorite

Apatite

Orthoclase

Quartz

Topaz

Corundum

Diamond

Luster: is the manner the mineral reflects light.
Color: each mineral has its basic colour for which it is known. But this is usually deceptive.
Streak: The color of the mineral in powdered form.
Cleavage: How the Mineral breaks along its plane of weakness.
Fracture: How the mineral breaks unevenly.

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GEO SOLUTIONS

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