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What are Diamonds?
Diamonds are a particular form of the chemical element Carbon - one of several forms, known as "allotropes" Other allotropes of carbon include graphite (used in pencil "leads"). Diamond is in fact a less stable form of Carbon than graphite, but under nornaml conditions, the conversion rate from diamond to graphite is so slow as to be negligible.
In terms of chemical bonding, diamond is known as giant covalent. Each carbon atom is bonded (by a shared pair of electrons) to 4 surrounding carbon atoms, with the surrounding atoms arranged in a tetrahedral arrangement (bond angle 109.5°), which corresponds to a face-centered cubic crystalline structure. A perfectly formed crystal of diamond, is thus a giant molecule consisting of many millions of Carbon atoms bonded together.
Because of its strong covalent bonds, and the large amount of energy required to break these bonds, diamond is know for its extreme hardness. Additionally, its structure also gives it the highest thermal conductivity of any bulk material.
A pure diamond will be clear, however diamond's structure can often be penetrated by impurities such as atoms of Nitrogen or Boron. These impurities, as well as defects that may arise in the structure, give some diamonds distinctive colors, including:
- Blue (because of Boron impurities)
- Yellow (because of Nitrogen impurities)
- Brown (because of lattice defects),
- Green (because of radiation exposure),
- Purple
- Pink
- Orange
- Red
- Natural diamonds are generally
formed as a result of extreme pressures and temperatures in the Earth's mantle, typically at depths of
87 to 118 miles (149 to 190 kilometers) - they become accessible, because they are brought closer
to the surface by volcanic eruptions.
Rough natural diamond: 
- There are two main processes by which synthetic (artificial) diamonds can be created - a HPHT (High Pressure High Temperature)
method which simulates conditions in the Earth's mantle, and a CVD (Chemical Vapor Deposition) method in which a gas of
carbon is deposited on a substrate, potentially allowing us to grow very large diamonds for industrial purposes.
Synthetic diamonds produced by the HPHT process: 
- As a gem stone
- Industrial applications - which usually have arisen to take advantage of diamond's extreme hardness and thermal
conductivity. Some industrial uses including using diamond as grinding grit, diamond cutters, diamond drills, using diamond for
making high performance bearings, and diamond containers for conducting
extremely high pressure scientific experiments (a "diamond anvil cell").
Scalpel with synthetic diamond blade: 
Articles
Brown Diamonds
Diamond Brands
Diamond Clarity
Diamond Clarity Enhancements
Diamond Colors
Diamond Color Grading
Diamond Cuts
Diamond Mines
Diamond Scams & Tricks
Diamond Shapes
Diamond Weights
Famous Diamonds
Flaws
Four C's
Inclusions
Industrial Applications
Simulant Diamonds
Synthetic Diamonds
What are Diamonds?
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