Gemstone
Introduction
A gemstone is a mineral, rock, or organic material that can be cut and polished to create jewelry or other adornments. Gemstones are often hard, but some soft minerals are used in jewelry because of their luster or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone.
Classification
Gemstones can be classified into different groups, species, and varieties. For example, ruby and sapphire are both varieties of the mineral species corundum. Other gemstones are classified purely by their color, such as a blue diamond.
Precious and Semi-Precious
In modern usage, the term "precious stones" are diamonds, rubies, emeralds, and sapphires. On the other hand, all other gemstones are considered "semi-precious," although there is no definitive demarcation between the two categories.
Value and Grading
The value of a gemstone is determined by a combination of its color, clarity, cut, and carat weight. This is commonly known as the "Four Cs." The grading of gemstones is a complex process which involves specialized knowledge and equipment.
Formation and Location
Gemstones are formed in various environments in the Earth's crust. The most important factor in the formation of gemstones is the presence of the necessary chemical elements in the right proportions and conditions. Some gemstones form in the Earth's mantle, like diamonds.
Synthetic and Imitation Gemstones
Synthetic gemstones are physically, optically, and chemically identical to the natural gemstone but are created in a laboratory. Imitation or simulated gemstones are chemically different but may look similar to the real thing.
Cutting and Polishing
Gemstones are cut and polished to bring out their natural beauty. The process of cutting is known as lapidary, and it involves cutting the gemstone into a particular shape and then polishing it.
Uses
Gemstones have been used for thousands of years for jewelry and decorative purposes. In addition, some gemstones are used for their supposed healing properties or mystical powers.