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
Robert S. Kerr (bishop) Robert S. Kerr (bishop) Robert Shaw Kerr (16 August 1917 - 18 November 1988) was seventh bishop of the Episcopal Diocese of Vermont, serving from 1974 to 1986. Kerr studied at Trinity College in Connecticut. Later he trained at the General Theological Seminary. Upon graduation, he was ordained deacon on February 28, 1943 by Bishop James De Wolf Perry of Rhode Island in Trinity church, Newport, Rhode Island. A year later he was ordained priest. Kerr served for some time as assistant at New York's cathedral of St John the Divine. He also served for some time as rector of