Most of our planet is made up of inorganic, mineral materials. Stone consists of minerals in the form of crystals, and it is estimated that there is 4000 times as much solid rock on the earth as there is water in all the oceans.

There are thousands of minerals. They can be characterized by colour, lustre, translucence, weight, hardness, their ability to split, and also by chemical formulae, each type of crystal having its own unique chemical structure. In common rock types there are only a few hundred different minerals, and in one single species there are seldom more than four or five different minerals. Granite is made up of the minerals quartz, feldspar and mica, the latter contributing sparkle. In only a few cases can minerals be found in a pure state.

The first use of minerals can be traced back to Africa in the production of colour pigments. These were retrieved from the earth through a simple form of mining.

In chemistry, minerals are classified according to their chemical composition. The most important groups include pure compounds: sulphides, oxides, carbonates and silicates. Most widespread are the silicates, whilst it is mainly oxides and sulphides that are used as ore for the extraction of metals. To simplify the picture one can reduce minerals into two groups: metals and non-metals.

The purer the mineral when extracted, the easier it is to use. However, most minerals are extracted from conglomerate rocks or different types of loose materials.

Certain minerals have a tendency to occur together in the natural environment. When looking for a certain mineral, it is usually very straightforward to work out where to find it.

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