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 Initiative the current drinking age. Radley Balko, of "Reason," wryly noted inconsistency opponents of the Amethyst Initiative believe that it "would be a "national tragedy" to, for example, allow 19- and 20-year-old men and women returning from Iraq and Afghanistan to have a beer in celebration of completing their tours of duty." Balko also noted research showing that underage drinking laws had not reduced highway deaths. In November 2008, the Student Senate at the University of Wisconsin–La Crosse rejected a proposal to urge that university's chancellor to sign the Amethyst Initiative. Supposedly the first such attempt by a student body to