All about Garnet

Introduction

Garnet, the birthstone for January, is actually a family of six minerals, each with similar chemical composition and a common crystal form. The most common colour is a deep red.

It is the state mineral of Connecticut, and New York's gemstone, and it signifies eternal friendship and trust.

 

Description of garnets

The stones come in a wide range of colours, including red, purple, orange, yellow, green and brown, and some are rarer than others. Although garnets are found worldwide, some varieties are unique to certain areas – for example, tsavorite is a green-coloured variety of the grossular garnet and is only found in the Tsavo area of Kenya. The most important sources for garnet are Africa, Sri Lanka, and India.

Garnets are extremely durable, but their hardness varies between 6.5 and 7.5 on the Mohs scale, depending on their chemical composition.

The different stones within the garnet family are as follows:

 

Name

Chemistry

Colour (and variety, if applicable)

Almandine

Iron aluminum silicate

Deep wine red

Pyrope

Magnesium aluminum silicate

Deep dead red

Grossular

Calcium aluminum silicate

Pale orange-pink (rosolite)

Electric green (tsavorite)

Massive green (transvaal jade)

Spessartine

Manganese aluminum silicate

Orange red / brown

Andradite

Calcium iron silicate

Topazolite (yellow or green)

Green (demantoid)

Black (melanite)

Uvarovite

Calcium chromium silicate

Bright green

 

Other varies of garnets, including malaya and rhodolite, are produced when the compositions of almandine and pyrope overlap. The rarest garnet of all is blue, and was discovered in the late 1990s in Bekily, Madagascar, and although extremely rare other blue garnets have been found in the United States, Turkey, Russia, Kenya and Tanzania.

 

History of garnets

Garnets have been in a staple in the gemstone world for centuries, and are commonly found in necklaces, rings, brooches, earrings, pendants and bracelets.

The name comes from the Middle English word gernet which meant "dark red" and from the Latin term granatus meaning grain or seed. For thousands of years, garnet has been considered a precious and valuable gemstone. The earliest instance of a garnet being found was in a royal Egyptian diadem dated back to around 3200 B.C. Garnet was also referenced in the Bible, with Noah using a garnet lantern was used by Noah to help him steer his ark through the dark.

Ancient explorers used garnets talismans to protect from evil and disaster, and the stone is said to be good luck when carried close to the body.

 

Value of garnets

The quality and value of a garnet depends on its colour and type, as well as its cut, clarity, and carat weight.

Because garnets are common on the gemstone and jewelry market, it's not difficult to find a relatively inexpensive but high quality stone. However, rarer forms of garnet, including saturated pure orange spessartine, can reach market values of over $2,000 per carat.

It is extremely rare to find a garnet with flawless clarity – most have some inclusions, but cleaner stones carry higher values.

 

Treatment of garnets

Garnet is unique in that it is rarely treated or created synthetically. Garnets on the market today are almost always 100 per cent natural, and this is what makes them especially attractive to collectors. Because most garnets are readily available, there is no need to create them by artificial means.

 

Summary

Garnets should be of interest to buyers who want an inexpensive yet high-quality gemstone.

The most common garnet is deep red with flecks of darker shades resembling seeds, but stones come in a wide variety of colours. As with any gemstone, pay attention to cut, clarity, colour and carats when determining a garnet's value.