Precious Stones Explained!Written by Sam Serio
The mineral to which term " precious stone" is applied, must be adaptable for jewelry or ornamental purposes and must possess beauty, hardness, and rarity.
The beauty of a precious stone or gem consists of its color or colorlessness, brilliancy or softness of luster, and transparency. To take a high and lasting polish, a mineral must be hard, —and many stones that would otherwise be highly valued are low in estimate of worth because they do not possess of sufficient hardness to make them endure wear and friction to which a precious stone is subjected when used in form of jewelry. The rareness of precious stones has a decided effect in determining their values. For instance, crocidolite, commercially known as tiger-eye, was sold by carat some years ago, and was largely used in making of fine jewelry. Today, this material is so plentiful that it is no longer classed among higher gems, but serves for cameos and intaglios like chalcedony and onyx.
The changes of fashion have much to do with determining market value of precious stones. Amethysts, topazes, cat's-eyes, aquamarines, alexandrites, and even emeralds and opals have been eagerly sought for at times and then again neglected for other gems, causing a sensible difference in value of these stones.
Sterling Silver Jewelry-The Rest Of The StoryWritten by Sam Serio
Silver is widely diffused but is rarely found in native state.
Silver is originally as widespread as gold, occurring in nearly all of volcanic rocks. Whereas gold remains unaltered by action of elements and is often carried long distances from its original place of occurrence, silver on contrary is only to be found in rocks where it originally occurs. When these rocks are broken down or worn away, silver is either driven into new mineral combinations, or more often dissipated and lost. Silver, therefore, is only to be obtained by subterranean mining. Shafts are driven and ore brought to surface, and by use of various processes silver is extracted, refined and made ready for commercial purposes.
An old process and one still employed extensively throughout Mexico where a large quantity of silver is produced, is to take ore after it has been crushed or reduced to a fine mud or puddle and spread it about two feet deep over floor of a large courtyard. Powered sulfate of copper is spread over mass and then horses or mules are driven around in circle to tread sulfate in and mix it thoroughly with ore. After about one day’s treading a quantity of common salt is added and after two days more treading quicksilver is added. This mass is trodden over for a period of about fifteen days, and is then shoveled into a large tank through which a rapid stream of water is passed. This washes away all but silver and quicksilver, which is then poured into cone-shaped canvas bags. Most of quicksilver runs out leaving silver, which is then retorted. The quicksilver is used over and over again to assist in recovering silver.