Speculum metal metal mixtures usually contain two parts copper to one part tin along with a small amount of arsenic, although there are other mixtures containing silver, lead, or zinc. The knowledge of making very hard white high luster metal out of bronze-type high-tin alloys may date back more than 2000 years in China although it could also be an invention of western civilizations. Such metals were used in sculpture and to make more effective mirrors than the more common yellow easily tarnishing bronze mirrors. In that era mirrors of speculum metal, or any precious metal, were rare and only owned by
Industrial rock sales and awards Industrial rock sales and awards This is a page containing all available sales and awards from industrial rock and industrial metal artists. This list is far from complete. Many countries were excluded from it because their Industry Associations lacked a searchable, online database. Belgium, Iceland and Mexico are some of them. Some European countries who do have it (Greece, Hungary and Spain) were excluded anyway, because their databases showed no relevant sales pertaining industrial rock and metal groups. Latin American countries with online databases (Argentina and Brazil) were excluded over the same principle. Below are the accreditations for the "Australian