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
William S. Bishop M. Gates in 1867. William S. Bishop William S. Bishop (ca. 1804 - June 6, 1863 Rochester, Monroe County, New York) was an American lawyer and politician from New York. He was a member of the New York State Assembly (Monroe Co.) in 1839. He was District Attorney of Monroe County from 1847 to 1850. On February 25, 1851, he married Ann Cornelia Rochester (1808–1893), daughter of Assemblyman Nathaniel Rochester (1752–1831). He was a member of the New York State Senate (27th D.) in 1854 and 1855. He died of pneumonia, and was buried at the Mount Hope Cemetery, Rochester.