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 woodstar Amethyst woodstar The amethyst woodstar ("Calliphlox amethystina") is a species of hummingbird in the family Trochilidae. It is found in most of central, and eastern South America proper, in Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Suriname-(the Guianas), Paraguay, Peru, and Venezuela. The bird's range surrounds the Amazon countries into the Andes foothills and higher elevations of upstream river systems, but is not along the Amazon River proper in the central Amazon Basin, or the central upper Basin; it is in Brazil at the river's outlet, and upstream for about 500 km. The amethyst woodstar's natural habitats are subtropical