Mineral

A mineral is a naturally formed solid that comes from the earth and is not made by living things. Minerals are found in rocks, soil, and even the ocean. They are the building blocks of most of the Earth's surface. There are over 4,000 known minerals, each with its own color, hardness, shape, and way of forming.

To be called a mineral, a substance must meet certain rules. It must occur naturally, be solid, have a fixed chemical formula, and have a regular, repeating structure of atoms called a crystal. For example, quartz is a mineral made of silicon and oxygen, while gold is a mineral made of a single element. Substances like water or coal are not minerals because they come from living things or are not solid.

Minerals are often grouped by their chemical composition and crystal structure. Some contain metals like iron, copper, or aluminum. Others are made of salts or silicates, which are combinations of silicon and oxygen with other elements. The shapes of minerals can be very beautiful, forming crystals with flat sides and sharp edges. People collect minerals for their appearance or use them in jewelry, such as diamonds and emeralds.

Each mineral has unique physical properties that help scientists identify it. These include color, luster (how it reflects light), hardness, streak (the color of its powder), and density. For instance, talc is one of the softest minerals and is used in baby powder, while diamond is the hardest known natural material. The Mohs hardness scale ranks minerals from 1 (softest) to 10 (hardest) to compare their strength.

Minerals are very important in everyday life. They are used to make buildings, machines, electronics, and even food. For example, salt (halite) is a mineral used for cooking, and iron is used to make steel. Minerals also provide elements like calcium, magnesium, and potassium, which are essential for healthy bodies.

Over millions of years, minerals form deep inside the Earth through heat, pressure, and chemical changes. Some form when lava cools down, others grow slowly from water solutions underground. These natural processes make minerals a record of Earth’s history, showing how the planet changes over time. Because of their beauty, usefulness, and variety, minerals are studied by geologists and loved by collectors around the world.