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Factors and Sizes of Crystals

Crystals are popular gems and people are finding a variety of uses for them. Holistic practitioners use them for healing and cleansing rituals. Crystals of different colors and sizes are used in decorating and jewelry-making. Builders and designers use them in interior design, as furniture embellishments and chandeliers. The scientific uses of crystals, aside from those in clocks, include electrical measurement, semiconductors made of silicon and electronic circuits. Other common uses include silicon solar cells, synthetic rubies for diodes and lasers and the many applications that utilize the hardness of diamonds.

Crystals Defined
- When considering the distribution of elements in the mineral world, the most common is crystal. Crystals are solids that are formed by a consistent repeated pattern of molecules that connect in formation. In some rocks, the arrangement of these building materials -- atoms and molecules -- can be different throughout the form. In crystals however, a collections of atoms are repeated in exactly the same arrangement throughout the entire material. This gives crystals their uniform color and symmetry.
Crystal Composition
- Since crystals are made up of atoms, their primary building blocks are protons, neutrons and electrons. When considering what influences the growth rate of crystals and what determines their eventual size, you have to understand crystal composition. A unit cell is the three-dimensional edifice that make up the crystal. Lattice is the collected arrangement of unit cells that are identical, and form the crystal's structure. Compressed oxygen atoms determine the crystal faces -- or edges.
Shape Factor
- The crystal form of any mineral is influenced by the mineral's internal construction. Scientists use the internal construction of crystals for identification. For instance, quartz forms are elongated and multi-faced, prisms are pyramid shaped and have six sides; galena and halite appear as cubes; and garnets develop 12 or 24 random dimensional sides. Interference from other minerals during the growth period can prevent crystals from becoming balanced in shape. The result is a mass without symmetrical form that developed with a minimum of smooth faces. This type is more common than well-formed crystals.
Crystal Size
- Since crystals are formed in the earth's center layers, there is an extreme amount of heat present. As the earth's stratum erupts from heat and spews magma, crystals are brought to the surface. Crystal size is governed by the formation's rate of cooling. Crystals continue to grow and form under excessive heat conditions. If the magma cools quickly, the crystals remain small. If the magma cools slowly, the crystals continue to grow. The longer the cooling period, the larger the crystal.

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