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
HMS Amethyst (1799) "Jonge Jacob". Captain Michael Seymour replaced Spranger. On 15 May 1807, "Amethyst" captured the privateer "Josephine" some 20 leagues from Scilly. "Josephine" was armed with four 2-pounders guns and small arms. She had a crew of 45 men, but had put ten on board "Jane", which had been sailing from Lisbon. "Josephine" had sailed from the Île de Batz and "Jane" was her only capture. When "Amethyst" captured "Josephine", "Amethyst" was in company with and . Then on 9 September "Amethyst" captured the Danish ship "Twende Venner". Later, on 18 October, "Amethyst" recaptured the ship "Susannah". "Amethyst" also recaptured the