Black Hills gold jewelry elsewhere. Pure 24 Karat gold bars, and stocks of pure silver and copper are the basic materials. These metals are not required to be mined in the Black Hills. Pure gold and other precious metal stock can be acquired from anywhere in the world. The finished jewelry known as Black Hills Gold must be "produced" in the Black Hills of South Dakota. The different colors of gold used for leaves and other details are made when the pure 24 Karat yellow gold is alloyed with copper to achieve the traditional 14 karat pink (or red) gold, and the gold is
Carat (mass) Carat (mass) The carat (ct) (not to be confused with the karat, sometimes spelled carat, a unit of purity of gold alloys), is a unit of mass equal to 200 mg (0.2 g; 0.007055 oz) and is used for measuring gemstones and pearls. The current definition, sometimes known as the metric carat, was adopted in 1907 at the Fourth General Conference on Weights and Measures, and soon afterwards in many countries around the world. The carat is divisible into one hundred "points" of two milligrams each. Other subdivisions, and slightly different mass values, have been used in the past in