Diamonds are transported to the surface by volcanic eruptions. The volcanic magma conduit is known as a kimberlitic pipe or diamond pipe. We find diamonds as inclusions in the (rather ordinary looking) volcanic rock known as kimberlitic. The kimberlitic magmas that carry diamonds to the surface are often much younger than the diamonds they transport (the kimberlitic magma simply acts as a conveyor belt). To ensure they're not converted to graphite, diamonds must be transported extremely quickly to the Earth surface. it's probable that kimberlitic lavas carrying diamonds erupt at between 10 and 30 kilometer / hour. Within the last few kilometers, the eruption velocity probably increases to several hundred kilometer / hr.
Diamond can be man made or altered to enhance their worth. Either method is legitimate, as long as it's disclosed to consumers.
Synthetics –. A diamond is simply crystallized carbon. Subjecting carbon to intense pressure and heat creates man-made diamonds. Most synthetics show a distinct pattern of color when viewed under ultraviolet light.
Laser Drilling -A laser beam can burn a tunnel through a diamond to reach dark spots or inclusions, which degrade a stone's value. The laser hole is then filled with acid to bleach the imperfection, creating the illusion of flawlessness.
Colored Diamonds –. Increasingly popular, color diamonds are quite rare in nature. But irradiation or combination of high heat and pressure can result in diamonds –. Either natural or synthetic –. In a rainbow of tints.
Fracture Filling –. The white blemish on the diamond is crack in the stone. Such Flaws can be distinguished when filled with a type of molten glass that refracts light much as a diamond does. Easily detectable, such fills may be temporary.
Pressure Treating –. A homely brown diamond can become a highly prized "colorless". Stone when subjected to extremely high heat and pressure. Trained gemologists can usually detect such improvements.
All natural diamonds are at least 990,000,000 years old. Many are 3,200,000,000 years old (3.2 billion years) how do you know this? Age: from Carbon dating works for very young carbon. You need to use other radioactive decay schemes (eg, uranium-lead) to date inclusions in diamonds.