One of nature's most unique and dazzling gifts, diamonds come from two types of deposits. Primary deposits generally consist of diamond-bearing "pipes" of a volcanic rock called "kimberlite." From deep in the earth these deposits were carried to the surface in molten rock, known as magma. Secondary deposits, also referred to as alluvial, were formed as a result of erosion of material from primary deposits and contain diamonds that have traveled some distance from their original source.
Even though world diamond production has tripled since 1980, diamonds remain a scarce resource. More than 12,000 kimberlite deposits have been found worldwide in the last 25 years, yet fewer than 1% have contained enough diamonds to make them economically viable. Geologists utilize many methods in diamond exploration, including satellite surveys, reconnaissance sampling and drilling in the ground. Some diamond producing countries include Botswana, Canada, Namibia, Russia, South Africa, Australia, and Tanzania.