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Precious stones.

Precious stones are defined as visually appealing gemstones created from rocks or minerals. Often used for jewelry and fashion accents, this term was created in the mid-1800’s to refer to four specific stones; diamonds, rubies, emeralds, and sapphires. All precious stones are translucent and are valued by the richness of their color, except for the diamond, which has a higher value based on being colorless.

_What is the difference between a precious stone and a semi-precious stone?

Precious stones and semi-precious stones are terms that were created in the mid-1800’s to describe gemstones, which were categorized solely based on their rarity. Stones found in abundance were labeled semi-precious, and a stone that was rare would be categorized as precious and more valuable. Diamonds, rubies, sapphires, emeralds were classified as precious stones. All other stones are classified as semi-precious stones. The distinction between precious and semi-precious stones are their rarity and their quality.

Despite this distinction and classification of precious stones vs. semi-precious stones, it is not necessarily true that a precious stones is always more valuable or rare than a semi-precious stone. For ex. a green garnet known as Tsavorite is classified as a semi-precious stone, however, it is more valuable than an emerald, which is classified as a precious stone.

List of precious stones.

_ Diamond.

The diamond is the most popular of all gemstones. The diamond is the highest valued precious stone, which takes millions of years to form. A diamond is a mineral compound made of pure carbon and is the hardest natural substance on the planet. Diamonds are so strong, they can only be cut or polished by another diamond. The name itself is derived from the Greek word “adamus,” which means “invincible.” Diamonds are typically colorless, but yellow, brown, green, gray, black, pink, blue, red, and purple stones can also be found along the diamond color spectrum. Jewelry-grade diamonds are rated based on color from bluish-white to yellow, and on clarity, which ranges from pure to various levels of flawed. Diamonds are measured in carats—the higher the carat weight and purity level of a stone, the more valuable the gem. The diamond is the birthstone for April.

_ Emerald.

Known for its brilliant green color, emerald can also have blue or yellow undertones and loses all color when subjected to high heat. Their brittle exterior makes emeralds difficult to shape.The earliest emeralds were mined in Upper Egypt as early as 2,000 B.C. They were mined throughout the reign of Alexander the Great and were well-loved and collected by Cleopatra. The Aztecs and Incas also coveted emeralds, and the Moguls of India revered them so much they inscribed the gems with sacred text to be used to ward off evil. Historically, emeralds have been mined from Russia, Austria, Australia, and Norway. Today, the majority of emeralds are found in Brazil, Zambia, and Colombia. The emerald is the birthstone for May.

_ Ruby.

The ruby is a pink to deep red precious gemstone. The name comes from the Latin word for red, ruber. Rubies are said to attract good luck for the wearer. Ancient Hindus believed rubies were a sign of protection from evil. Today, the ruby has come to symbolize love and passion. Rubies were also highly prized by ancient Chinese warriors who were known to wear rubies on their armor. Most rubies today are mined in Africa and Southeast Asia. The largest mined ruby weighing in at four pounds, the Liberty Bell Ruby, was stolen in a heist in 2011. The ruby is the birthstone for July.

_Sapphire.

Sapphires come in a variety of colors, but are mostly associated with blue hues. A sapphire of another color, like pink, white or yellow, is generally called a fancy sapphire. The blue sapphire represents peace and serenity. It is seen many times in ancient religious writing to symbolize purity, wisdom, loyalty and faith. Sapphires are mined throughout Africa and Asia, but can be found in Australia and the U.S. The sapphire is the birthstone for September.

_Semi-precious stones.

1-Alexandrite.

Alexandrite results from small scale replacement of aluminium by chromium ions in the crystal structure, which causes intense absorption of light over a narrow range of wavelengths in the yellow region (580 nm) of the visible light spectrum. Because human vision is more sensitive to light in the green spectrum and the red spectrum, alexandrite appears greenish in daylight where a full spectrum of visible light is present and reddish in incandescent light which emits less green and blue spectrum.

2-Amethyst.

Amethyst is a semiprecious stone and is the traditional birthstone for February.

3-Aquamarine.

Aquamarine is a blue or cyan variety of beryl. It occurs at most localities which yield ordinary beryl. The gem-gravel placer deposits of Sri Lanka contain aquamarine. Clear yellow beryl, such as that occurring in Brazil, is sometimes called aquamarine chrysolite. The deep blue version of aquamarine is called maxixe.

4-Citrine.

Citrine, the most common reference for which is certain coloured varieties of quartz which are a medium deep shade of golden yellow. Citrine has been summarized at various times as yellow, greenish-yellow, brownish yellow or orange.

5-Garnet.

Garnets are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives.

6. Grossular.

Grossular is a calcium-aluminium mineral species of the garnet gemstone group with the formula.

7-Pyrope.

The mineral pyrope is a member of the garnet group. Pyrope is the only member of the garnet family to always display red colouration in natural samples, and it is from this characteristic that it gets its name: from the Greek for fire and eye.

8-Amandine.

Almandine is an iron alumina garnet, of deep red color, inclining to purple. It is frequently cut with a convex face, or en cabochon, and is then known as carbuncle.

9-Rhodalite.

is a varietal name for rose-pink to red mineral pyrope, a species in the garnet group.

10-Iolite.

The name Iolite comes from the Greek word ‘Ion’, which means ‘Violet’. Iolite is often confused with Tanzanite because of its similarity in color. Generally, Iolite is a deeper shade of violet, with hues ranging from deep blue, purple, lavendar, and gray-blue.

11-Onyx.

Onyx is a banded variety of the oxide mineral chalcedony.

12-Opal.

Opal is a very popular gemstone, mainly due to its wonderful variety of rich and beautiful colors. One of the extraordinary features of this gemstone is called Opalescence. Opalescence is a kind of light play that happens with certain high quality stones. Light reflects and bounces around the very small structures of the stone, giving it a wonderful aura and sometimes iridescence.

13-Pearl.

A Pearl is an organic gem, produced when certain mollusks, primarily oysters cover a foreign object with beautiful layers of nacre. A good sized Pearl can take between five to eight years to form, which is usually the entire life of the oyster or mollusk.

14-Peridot.

The Peridot is a very old but still very popular gemstone.

15-Tanzanite.

Tanzanite is an extraordinary and beautiful gemstone. Tanzanite is a blue variety of the gemstone zoisite discovered in 1967 at Merelani Hills in Tanzania.

16-Topaz.

Topaz is a member of Quartz family. This beautiful gemstone most commonly found in yellow color. A Topaz turns a vivid blue when exposed to heat. Also the Topaz is said to have power of changing color when it’s near poison. The name topaz is derived from the Sanskrit word ‘Tapas’, meaning ‘Fire’.

17-Tourmaline.

Tourmalines are gemstones with deep brilliance and incomparable variety of colors. These Gemstones are mixed crystals of aluminium boron silicate with a complex and changing composition.

References :

Precious Stones Sapphire, Emerald, Diamond, and Ruby”, jewelryinfoplace.com

Types of Gemstone”, www.geologypage.com

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