This material is sieved through a series of screens that allow the miner to separate and discard the extremely large cobbles as well as the very fine grained sand, silt and clay. The miner extracts the sapphire bearing rock with the larger tools. The fee locality operators allow only the use of hand tools such as picks, shovels, crowbars, gads and wedges. The prospector pays a set fee for the right to extract a given weight or volume of sapphire bearing rock or gravel. There are several such fee locality sapphire mines in Montana that have been profitable for both the mine owners and the prospectors who have chosen to pay the fee.
Labor and mining costs have been very high in the United States and the Yogo Gulch mines have generally not been profitable for the operators.įee localities are areas where one can pay a set fee for the privilege to extract gems and minerals from mines or claims that are owned by a second party. In the United States, the Yogo Gulch area in Montana has historically produced some fine sapphires but few of these attain the size of the fine Kashmir gems. Sapphires have been found in many other places in the world but few have attained the desirability of the Kashmir stones. Geographic isolation, political instability and high demand all combines to make these stones very expensive. These stones are rare and the finest examples come from Kashmir, a mountainous area in northern India on the Pakistan border. Supply and demand has dictated that cornflower blue sapphires are the most expensive. Except for color, all of the other physical and optical properties of sapphire are identical to those of ruby and you are referred to the ruby page for these data. In the simplest terms, corundum that is any color other than red is a sapphire. In the United States "pink rubies" are eliminated from the gem trade by legal definition. If corundum is pink, the United States Federal Trade Commission requires that the stone be sold as a sapphire. Rubies are red to orange-red to purplish red. Sapphire's companion variety of corundum is ruby. The axes are arranged in a hexagonal crystal, a crystal with four axes, three of which are of equal length and intersect at 60 degree angles, and one of which is unequal in length to the others and intersects the others at a right angle. Sapphire is a variety of corundum or aluminum oxide and Al203 gives its chemical formula-that is, two parts of Aluminum to three parts of Oxygen. If you were born in the month of September, sapphire is your birthstone.
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