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The amazing phenomenon of crystallization everywhere from crevices between rock to geodes. Geodes

are hollow rocks in which mineral deposits are found.

Sometimes crystal formation also takes place in them.

Crystals are one of the most interesting things man ever

discovered. The interest in crystals has not changed through

many generations. Even now, every child dreams of finding a

very big crystal to play with.

From our ancestors to millenials, all of humankind has been

fascinated by crystals. In today’s time, jewellery without crystals or Tanush Joshi (VII)

gemstones is like a cake without icing. Transparent crystals display

different colours when light passes through them. Crystals can be of

different shapes and sizes. Let us learn more about crystals and their

formation. Crystallization is the natural or artificial process by which

a solid forms, where the atoms or molecules are highly organized into

a structure known as a crystal. Crystals are solids in which

atoms/molecules/ions are present in an orderly manner. Single

crystals can be identified by their geometrical shapes and flat faces.

Crystallization occurs in two major steps.

� Nucleation. - This is the first step. Nucleation can take place in

supercooled liquids or in supersaturated solution.

� Crystal growth. - This is the second step. During this process,

the particles in the solution grow in size in an orderly manner,

leading to the formation of crystals. Crystal formation can be

achieved by various methods, such as cooling, evaporation, addition

of a second solvent, solvent layering, sublimation as well as other

methods. Quartz, Amethyst, Aquamarine are examples of crystals.

The most common crystals are hexagonal in shape and are found