Overview
About Garnet
Adorned the necks of Egypt’s pharaohs and entombed together as prized possessions in the afterlife, Used as a signet ring to stamp wax on secured documents in Ancient Rome, Garnets have been widely traded and favoured by nobles and clergy. “Carbuncle” is the term often used for red garnets and it is believe to be one of the 4 precious gem given to King Solomon by God. It comes in many different variants and all colours. Explore our collection of garnets here.
Garnet Properties
Mineral: Garnet
Chemistry:
- Almandine (Fe3Al2(SiO4)3)
- Andradite (Ca3Fe2(SiO4)3)
- Grossular (Ca3Al2(SiO4)3)
- Pyrope (Mg3Al2(SiO4)3)
- Rhodolite ((Mg, Fe)3Al2(SiO4)3)
- Spessartine (Mn3Al2(SiO4)3)
Refractive Index: 1.714 – 1.888
Birefringence: none
Specific Gravity:3.47 – 4.15
Mohs Hardness:6.5 – 7.5
Main Colours
Red
Other Colours
All Other Colours
Common Shapes
Birthstone Month
January
Treatments / Enhancements
Heat Treatment is usually used to improve colour and clarity
Origins
United States, Madagascar, Tanzania, Russia, Kenya, Turkey
Colour
Colour is the most significant factor affecting the value of a garnets.
Garnets are a group that includes a number of different minerals, so appearances vary widely. Buyers have to be aware of the types of garnets. Learning about the large variety of garnets can be daunting, but it is much easier to recognise them from their colour.
Garnets with different undertones
Colour Grades of Garnets
Garnets not only have different colour/undertone shades, they also come in colour shades with varying intensity as well. Below is some of the Garnets with different shade intensity.
Vivid
Intense
Medium Intense
Light
Types of Garnets
Garnet group is form by a group of garnets with different chemical formulas, which results in them having distinct and varying colours. Using colour is probably the most easiest way to distinguish between the different garnets.
Almandine
Almandine is the gem most commonly known as “Carbuncle”, the latin word for live coal or burning coal. These gems are easily distinguishable by their vivid purple to orangey red hues that accompanies it. It also have many nicknames like Oriental Garnet, Almandine Ruby, Carbuncle, Precious Garnet
Spessartine
Spessartine or Spessartite is a garnet with Manganese and Aluminium. It has its name derived from Spessart, a range of low mountains in Bavaria. Spessartine is easily distinguishable by their various orange hues. The term “Mandarin Garnet” is used as the trade name for this garnet
Pyrope
Pyrope garnets derived from the greek word “pyropos”, meaning firelike and the colour of the gem reflects this very well. It often have colours varying from deep red to black. Tradenames for Pyropes include: Cape Ruby, Arizona Ruby, California Ruby, Rocky Mountain Ruby, and Bohemian Ruby
One of the more known pyrope variety is Rhodolite, greek word for rose, a violet red garnet with mixed properties from Almandine and Pyrope.
Andradite
Andradites are a variety of garnets that contain calcium and iron within it. It exists in 3 different colours. A black variety called Melanite, a yellow green variety called Topazolite and the more known green variety, Demantoid.
Demantoids is one of the most prized garnets out of all the garnets due to its exceptionally beautiful green hue.
Grossular
Grossular Garnets are garnets that contain calcium and aluminium within them. Its name is derived from “Grossularia”, the botanical name for gooseberry, due to it having a green colour hue. Under grossular garnets, there are 2 varieties, namely Hessonite and Tsarvorite.
Hessonites, the cinnamon brown variety, derived its name from the greek word, “hessonite” , which means inferior due to the garnet being not as hard as Zircon.
Tsavorite, the green variety, derived its name from the location it has been discovered, the Tsavo area in Kenya.
Clarity
Clarity of a gem is judged based off the gem’s opacity and how much inclusions does the gem contain. The assessment of clarity is often done thru eye clean and it follow the same grading as with diamonds. Inclusions within the gem affects the value of the gem. The more visible the inclusions are to the visible eye, the lower the value of the gem.
Garnets sold for jewelry has inclusions that can only be seen under magnification. Any eye visible inclusions decreases the gems value. Different garnets have different degree of visible inclusions. red garnets usually do not have eye-visible inclusions while orange garnets can often include eye-visible inclusions. Inclusions that might pose durability problems as well, causing fractures and lowering garnet’s value significantly.
Clarity Grades of Garnets
Clarity in transparent Garnets is assessed by naked eye only and at distance of about 40cm. Garnets are classified as type 2 stones. This means that there are eye clean, meaning that theres usually no visible inclusions within the gem.
Special Inclusions
Some inclusions within different garnets can raise its value instead of decreasing it. It also give the garnet a very distinct look, making it special and more appealing.
Hessonite garnets often have a turbulent appearance on the inside of the gem. This is called the roiled affect. It contain many small darker inclusions which make the gem look like it have different shades of orangey red within it.
Demantoids often have inclusions in the gem. These inclusion are called Horsetails. These inclusions appear to be many fiber like inclusions that spread out on the gem. This give the demantoid a very distinct and unique appearance which increases the value of the gem.
Cut
Garnets are often cut into shapes that can be easily used in settings and jewellery. This means that its often comes in standard shapes. This is especially true for red garnets, the most commonly found garnet. For the more expensive garnets, such as Tsavorites, they are cut in ways that allow for more weight can be retain from the rough. Demantoids are often cut into exact proportions to allow for its shine and fire to be fully maximised. Garnets are usually cut into beads and cabochons and they also are highly transparent.
Carat
Gemstones such as Garnets are denser than diamonds, therefore the carat weight for a gemstones differs from that of a diamond. Size of gemstones, including Garnets, are measured by carat as well as their diameter in millimetres. However, Garnets are more valued for their colour, cut and clarity.
Garnets usually can be found in most sizes and weights due to its availability. Garnets such as Tsavorite and Demantoid often come in much smaller sizes. This means that they will have a higher price per carat compared to the other garnets, which readily come in larger sizes
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