Crystals are objects or solid materials that are formed from atoms and molecules that are arranged in a very orderly fashion. This internal structure makes crystals unique from each other but the arrangement of the small components are very specific and recognizable when viewed under a microscope.
With the highly arranged components of crystals, these materials are often classified into different types depending on their structure’s shape or so-called lattices. Crystal solids that have cube-like structures are also referred to as isometric crystals because of the almost even distribution of the atoms and ions on all sides. These cubic crystals may either have 8 or 10 faces indicating the alignment of its components. Another type of crystal is called the tetragonal crystal. This type is similar to the cubic type but its structure includes a long axis on one side resulting to the creation of double pyramid shapes. Crystals that have prisms with 6 sides are called hexagonal crystals. When the cross section is viewed in a microscope, the hexagonal pattern will become very obvious. There are also crystals that have double pyramid structures but seem to be aligned with each other or form one rhombic prism. Crystals with this structure are referred to as orthorhombic.
Many gemstones that people are familiar about are crystals by nature. These gemstones include diamonds, rubies, sapphires, and emerald stones. Aside from these stones, many common items are also formed with a highly organized structure and arrangement of components like ions, atoms, and molecules. Snowflake and the standard table salt are basic example of crystals. When viewed closely, these everyday or simple items have a clear and organized structure of its component ions and atoms. Most crystals like gemstones can be found on rocks and beneath the Earth’s surface. Crystals may sometimes be formed organically through animals like mollusks for example. These animals may produce calcite and aragonite which are classified as organic crystal solids.