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
Geology of Pakistan 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 entity. Baluchistan province is the richest in mineral resources available in Pakistan. While recently Sindh discovered coal deposits in Thar. Khyber Pakhtunkhwa is rich in gems. Most of the mineral gems found in Pakistan exist here. Apart from oil, gas and some mineral used in nuclear energy purposes