Amethyst even if the iron concentration is low. Natural amethyst is dichroic in reddish violet and bluish violet, but when heated, turns yellow-orange, yellow-brown, or dark brownish and may resemble citrine, but loses its dichroism, unlike genuine citrine. When partially heated, amethyst can result in ametrine. Amethyst can fade in tone if overexposed to light sources and can be artificially darkened with adequate irradiation. Amethyst was used as a gemstone by the ancient Egyptians and was largely employed in antiquity for intaglio engraved gems. The largest Ancient Egyptian amethyst mines are located at Wadi el-Hudi and those mines may be the
Amethyst gasfield were built in 1989 by UiE Scotland in Glasgow, and have 5 and 6 wells respectively in Amethyst East. B1D and C1D were built in the following two years and currently produce from 4 and 7 wells in Amethyst East and Amethyst West respectively. C1D is connected to A1D and B1D is connected to A2D. All Amethyst daily operation and processing is carried out onshore. Personnel only travel to the platforms themselves for maintenance and well work. Produced gas is transported to the Easington Gas Terminal and sold to Électricité de France. Amethyst gasfield Amethyst is a natural gas field