Precious Stones Explained!

Written by Sam Serio

The mineral to whichrepparttar 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 inrepparttar 145809 estimate of worth because they do not possess of sufficient hardness to make them endurerepparttar 145810 wear and friction to which a precious stone is subjected when used inrepparttar 145811 form of jewelry. The rareness of precious stones has a decided effect in determining their values. For instance,repparttar 145812 crocidolite, commercially known as tiger-eye, was sold byrepparttar 145813 carat some years ago, and was largely used inrepparttar 145814 making of fine jewelry. Today, this material is so plentiful that it is no longer classed amongrepparttar 145815 higher gems, but serves for cameos and intaglios like chalcedony and onyx.

The changes of fashion have much to do with determiningrepparttar 145816 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 inrepparttar 145817 value of these stones.

Sterling Silver Jewelry-The Rest Of The Story

Written by Sam Serio

Silver is widely diffused but is rarely found inrepparttar native state.

Silver is originally as widespread as gold, occurring in nearly all ofrepparttar 145808 volcanic rocks. Whereas gold remains unaltered byrepparttar 145809 action ofrepparttar 145810 elements and is often carried long distances from its original place of occurrence, silver onrepparttar 145811 contrary is only to be found inrepparttar 145812 rocks where it originally occurs. When these rocks are broken down or worn away,repparttar 145813 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 andrepparttar 145814 ore brought torepparttar 145815 surface, and by use of various processesrepparttar 145816 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 takerepparttar 145817 ore after it has been crushed or reduced to a fine mud or puddle and spread it about two feet deep overrepparttar 145818 floor of a large courtyard. Powered sulfate of copper is spread overrepparttar 145819 mass and then horses or mules are driven around in circle to treadrepparttar 145820 sulfate in and mix it thoroughly withrepparttar 145821 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 butrepparttar 145822 silver and quicksilver, which is then poured into cone-shaped canvas bags. Most ofrepparttar 145823 quicksilver runs out leavingrepparttar 145824 silver, which is then retorted. The quicksilver is used over and over again to assist in recoveringrepparttar 145825 silver.

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