Gemstones

Diamonds

Diamonds were first mined in India.^[7] Pliny may have mentioned them, although there is some debate as to the exact nature of the stone he referred to as Adamas;^[8] In 2005, Australia,Botswana, Russia and Canada ranked among the primary sources of gemstone diamond production.^[9][10]

The British crown jewels contain the Cullinan Diamond, part of the largest gem-quality rough diamond ever found (1905), at 3,106.75 carats (621.35 g).

Now popular in engagement rings, this usage dates back to the marriage of Maximilian I to Mary of Burgundy in 1477.^{[citation needed]}

^{Many precious and semiprecious stones are used for jewellery. Among them are:}

^Amber

Amber, an ancient organic gemstone, is composed of tree resin that has hardened over time. The stone must be at least 1 million years old to be classified as amber, and some amber can be up to 120 million years old.

Amethyst

Amethyst has historically been the most prized gemstone in the quartz family. It is treasured for its purple hue, which can range in tone from light to dark.

Emerald

Emeralds are one of the three main precious gemstones (along with rubies and sapphires) and are known for their fine green to bluish green colour. They have been treasured throughout history, and some historians report that the Egyptians mined emerald as early as 3500 BC.

Jade

Jade is most commonly associated with the colour green, but can come in a number of other colours as well. Jade is closely linked to Asian culture, history, and tradition, and is sometimes referred to as the stone of heaven.

Jasper

Jasper is a gemstone of the chalcedony family that comes in a variety of colours. Often, jasper will feature unique and interesting patterns within the coloured stone. Picture jasper is a type of jasper known for the colours (often beiges and browns) and swirls in the stone’s pattern.

Quartz

Quartz refers to a family of crystalline gemstones of various colours and sizes. Among the well-known types of quartz are rose quartz (which has a delicate pink colour), and smoky quartz (which comes in a variety of shades of translucent brown). A number of other gemstones, like Amethyst and Citrine, are also part of the quartz family. Rutilated quartz is a popular type of quartz containing needle-like inclusions.

Ruby

Rubies are known for their intense red colour, and are among the most highly valued precious gemstones. Rubies have been treasured for millennia. In Sanskrit, the word for ruby is ratnaraj, meaning king of precious stones.

Sapphire

The most popular form of sapphire is blue sapphire, which is known for its medium to deep blue colour and strong saturation. Fancy coloured sapphires in various colours are also available. In the United States, blue sapphire tends to be the most popular and most affordable of the three major precious gemstones (emerald, ruby and sapphire).

Turquoise

Turquoise is found in only a few places on earth, and the world’s largest turquoise producing region is the southwest United States. Turquoise is prized for its attractive colour, most often an intense medium blue or a greenish blue, and its ancient heritage. Turquoise is used in a great variety of jewellery styles. It is perhaps most closely associated with southwest and Native American jewellery, but it is also used in many sleek, modern styles. Some turquoise contains a matrix of dark brown markings, which provides an interesting contrast to the gemstone’s bright blue colour.

Necklace

Necklaces have been an integral part of jewelry since the time of ancient civilizations. The birth of necklaces is believed to be as old as the Stone Age, which is around 40,000 years old. At that time, people were decorating themselves with mollusk necklaces. Later, necklaces made of stones, bones, shells and animal teeth became popular. After the discovery of metals, gold, silver and a variety of other metals were used to make eye-catching necklaces for both men and women.^[1]

Types of necklaces

Bib necklace

A bib necklace is made multiple strands of stepped pearls.

Choker

35 centimetres (14 in) to 43 centimetres (17 in) long and sits high on the neck.

Opera necklace

An opera necklace is 75 centimetres (30 in) to 90 centimetres (35 in) long and sits at the breastbone.

Princess necklace

A princess necklace is 45 centimetres (18 in) to 50 centimetres (20 in) long. It is between choker and matinee length.

Sautoir or rope necklace

A sautoir or rope necklace is any necklace longer than opera length.

Uniform necklace

A uniform necklace consists of pearls that appear to be all the same size, although normally there is a slight difference towards the ends so they appear to be in proportion.

Sharktooth

A sharktooth necklace is a necklace with a shark tooth attached.

Gemstone

A gemstone or gem (also called a precious or semi-precious stone, or jewel) is a piece of attractive mineral, which—when cut and polished—is used to make jewelry or other adornments.^[1]However certain rocks, (such as lapis-lazuli) and organic materials (such as amber or jet) are not minerals, but are still used for jewelry, and are therefore often considered to be gemstones as well. Most gemstones are hard, but some soft minerals are used in jewelry because of their lustre or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone. Apart from jewelry, from earliest antiquity until the 19th century engraved gems andhardstone carvings such as cups were major luxury art forms; the carvings of Carl Fabergé were the last significant works in this tradition.

Characteristics and classification

he traditional classification in the West, which goes back to the Ancient Greeks, begins with a distinction between precious and semi-precious stones; similar distinctions are made in other cultures. In modern usage the precious stones are diamond, ruby, emerald and sapphire, with all other gemstones being semi-precious.^[2] This distinction is unscientific and reflects the rarity of the respective stones in ancient times, as well as their quality: all are translucent with fine color in their purest forms, except for the colorless diamond, and very hard,^[3] with hardnesses of 8-10 on the Mohs scale. Other stones are classified by their color, translucency and hardness. The traditional distinction does not necessarily reflect modern values, for example, while garnets are relatively inexpensive, a green garnet called Tsavorite, can be far more valuable than a mid-quality emerald.^[4] Another unscientific term for semi-precious gemstones used in art history andarchaeology is hardstone. Use of the terms 'precious' and 'semi-precious' in a commercial context is, arguably, misleading in that it deceptively implies certain stones are intrinsically more valuable than others, which is not the case.

In modern times gemstones are identified by gemologists, who describe gems and their characteristics usingtechnical terminology specific to the field of gemology. The first characteristic a gemologist uses to identify a gemstone is its chemical composition. For example, diamonds are made of carbon (C) and rubies ofaluminium oxide (Al₂O₃). Next, many gems are crystals which are classified by their crystal system such ascubic or trigonal or monoclinic. Another term used is habit, the form the gem is usually found in. For example diamonds, which have a cubic crystal system, are often found as octahedrons.

Gemstones are classified into different groups, species, and varieties. For example, ruby is the red variety of the species corundum, while any other color of corundum is considered sapphire. Emerald (green), aquamarine (blue), bixbite (red), goshenite (colorless), heliodor (yellow), andmorganite (pink) are all varieties of the mineral species beryl.

Gems are characterized in terms of refractive index, dispersion, specific gravity, hardness, cleavage, fracture, and luster. They may exhibitpleochroism or double refraction. They may have luminescence and a distinctive absorption spectrum.

Material or flaws within a stone may be present as inclusions.

Costume Jewelry

Costume jewelry (also called fashion jewelry, junk jewelry, fake jewelry, or fallalery) is the first jewelry (jewellery) manufactured as ornamentation for the masses to complement a particular fashionable garment or "costume".^[2] Costume jewelry came into being in the 1930s as a cheap, disposable accessory meant to be worn with a specific outfit. It was intended to be fashionable for a short period of time, outdate itself, and then be repurchased to fit with a new outfit or new fashion style.^[3] Its main use is in fashion, as opposed to "real" (fine) jewelry which may be regarded primarily as collectibles, keepsakes, or investments. Costume jewelry is made of less valuable materials including base metals, glass, plastic, and synthetic stones; in place of more valuable materials such as precious metals and gems.

Etymology

he term costume jewelry dates back to the early twentieth century. It reflects the use of the word "costume" to refer to what is now called an "outfit"; for example, a "handsome street costume of maroon brown velvet". Costume jewelry is meant to complement a particular fashionable garment or "costume"; Hence the name, "costume jewelry".^[2]

Components

Originally, costume or fashion jewelry was made of inexpensive simulated gemstones, such asrhinestones or lucite, set in pewter, silver, nickel or brass. During the depression years, rhinestones were even down-graded by some manufacturers to meet the cost of production.^[2] Modern costume jewelry incorporates a wide range of materials. High end crystals, cubic zirconia simulated diamonds, and some semi-precious stones are used in place of precious stones. Metals include gold- or silver-plated brass, and sometimes vermeil or sterling silver. Lower-priced jewelry may still use gold plating over pewter, nickel or other metals; items made in countries outside the United States may contain lead. Some pieces incorporate plastic, acrylic, leather or wood.