Gemstone irradiation produce mixtures of blue and yellow-to-brown colors, so heating is required as an additional procedure to remove the yellowish color. In some cases, the new colors induced by artificial irradiation may fade rapidly when exposed to light or gentle heat, so some laboratories submit them to a "fade test" to determine color stability. Sometimes colorless or pink beryls become deep blue upon irradiation, which are called Maxixe-type beryl. However, the color easily fades when exposed to heat or light, so it has no practical jewelry application. Gemstone irradiation The gemstone irradiation is a process in which a gemstone is artificially
Mining in Pakistan Mining in Pakistan Mining is an important industry in Pakistan. Pakistan has deposits of several minerals including coal, copper, gold, chromite, mineral salt, bauxite and several other minerals. There are also a variety of precious and semi-precious minerals that are also mined. These include peridot, aquamarine, topaz, ruby, emerald, rare-earth minerals bastnaesite and xenotime, sphene, tourmaline, and many varieties and types of quartz The Pakistan Mineral Development Corporation is the responsible authority for the support and development of the mining industry. Gemstones Corporation of Pakistan looks after the interests of stake holders in gemstone mining and polishing as an official