Gemstone value of the stone. Some treatments are used widely because the resulting gem is stable, while others are not accepted most commonly because the gem color is unstable and may revert to the original tone. Heat can improve gemstone color or clarity. The heating process has been well known to gem miners and cutters for centuries, and in many stone types heating is a common practice. Most citrine is made by heating amethyst, and partial heating with a strong gradient results in “ametrine” – a stone partly amethyst and partly citrine. Aquamarine is often heated to remove yellow tones, or
Ron Stone (bishop) Ron Stone (bishop) Ronald Francis "Ron" Stone AM (born 10 September 1938) was the tenth Bishop of Rockhampton in the Anglican Church of Australia from 1996 to 2003. Stone was educated at Taylors College, Melbourne and ordained in 1963. His first post was as a curate at Junee, after which he was priest in charge of Kameruka. He was rector of Kerang and then the Archdeacon of Bendigo. He was ordained to the episcopate as an assistant bishop in Tasmania before becoming Bishop of Rockhampton in 1996. He retired from this position in 2003 and is currently the vicar-general in