Minerals Everywhere
It takes a lot of ingredients to make biscuits – flour, milk, eggs, butter, and sugar. Everything is all mixed together. A rock is like that. Rocks are mixtures of materials called minerals. There are about 2,000 kinds of minerals. Some are hard, some are soft, some are shiny, and some are sparkly. Many of them are mixed with other minerals. But some are found in chunks, small lumps, or broad patches between layers of other kinds of rocks.
Most kinds of minerals are made up of tiny shapes called crystals. Crystals have flat sides and sharp corners. The salt we put on food is a mineral called halite. It is made up of crystals shaped like cubes. Quartz crystals have beautiful pointed shapes. Sulphur crystals look like chunks of bright yellow glass. Pure mercury is a mineral that stays melted, even when cool. Mercury is used in some thermometers. Uranium has flat sides and a dull colour. It is never found alone, but always is mixed with other minerals. Uranium is sometimes used as a fuel in making electricity.
Picture Credit : Google
