A crystal can be defined as a repeating, three dimensional arrangement of atoms, molecules or ions. Any solid material, even DNA can crystallize. The center of our planet was once thought to a large, single iron crystal but now modern studies show that the inner core is an aggregate of smaller crystals instead of a single solid.
Quick Facts: –
- The process of crystallization takes place in nature when liquid cools and start to harden. A few molecule gather together when they try to become stable.
- There are 4 types of crystals: – ionic, molecular, covalent, metallic.
- Most of the valuable crystals like: – diamond, ruby, etc. are formed when liquid rock, called magma cools and starts to harden.
- Crystals can be produced by some living organisms.
- A crystal can have sharp edges as well as very flat surface. These surfaces are called facets.
- They can take any geometric shape like: – square, triangle, rectangle etc.
- There are 7 basic shapes of crystal that are called lattice. They are: – Cubic, Trigonal, Triclinic, Orthorhombic, Hexagonal, Tetragonal and Monoclinic.
- Diamonds are just one giant molecule made from a lot of atoms of a single element.
- Liquid crystals are used in computers for their display.
- Hardness or softness of a crystal depends on the number and strength of the bonds with adjoining atoms.
- The largest known gem diamond is the Cullinan Diamond. It weighed nearly around 3,106 carats. It was discovered in 19005 in South Africa.
- Sugar and Salt are the most common crystals.
- Snowflakes are formed in the cloud. They are ice crystals.
- Crystals do not always grow naturally. Sometimes they are produced in lab by scientists under controlled conditions.