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
Mariano S. Bishop others in New England with 70,000 Southerners as well, improving wages and conditions greatly. Bishop became one of the directors of the TWUA in 1943 and became international executive vice president in 1952. Bishop died suddenly at 46 on January 2, 1953, suffering a heart attack on the way to a union meeting in New Jersey. His funeral in Fall River was said at the time to have been the largest in city history. Known in his day in his hometown as "The Most Important American of Portuguese Descent," Bishop remains an important figure of Portuguese-American heritage. Mariano S. Bishop