Precious metal "precious" metal can also be determined by high demand or market value. Precious metals in bulk form are known as bullion and are traded on commodity markets. Bullion metals may be cast into ingots or minted into coins. The defining attribute of bullion is that it is valued by its mass and purity rather than by a face value as money. The level of purity varies from issue to issue. "Three nines" (99.9%) purity is common. The purest mass-produced bullion coins are in the Canadian Gold Maple Leaf series, which go up to 99.999% purity. A 100% pure bullion is
Aurum, Nevada locally as "Doughburg." On February 11, 1884, an avalanche occurred in Silver Canyon, above the boarding house of the Sadie L Mine. Three people were killed. Two of the victims, H. W. Mickel, and Wallace McCrimmon, were buried at Aurum. The other victim, John Fox, was taken into Cherry Creek for burial. Over the following decades, the community experienced multiple periods of boom and bust. During booms, the community's population rapidly swelled to hundreds of people. However, during busts, miners left, businesses closed, and the population rapidly dwindled. During one of these "busts", the population dropped to only one inhabitant