It sounds quite dull initially, right? All you think of is that nasty brownish red stone set in some cheap old fashioned setting at the back of your jewellery box. But like most other gemstones it has some spectacular and less well known varieties and hopefully after reading about a few of them, hearing the word garnet will no longer induce a shudder of antipathy.
Garnets are a group of gems, which are divided into species and then sub-divided into varieties, but some of the species can mix to create hybrid garnets varieties. Most garnets are not chemically pure, but a mixture of two or perhaps three species all mingled together like eggs, milk and flour in a cake mix. Anyway, I’ll spare you the complicated geeky babble and move straight onto describing some of the more popular varieties available using their commonly used trade names.
Rhodolite garnet – this is the name given to any purplish red variety of the pyrope - almandine garnets. It’s a relatively hard garnet (7.5 on the Mohs scale) with good toughness so is a good choice for most jewellery.
Spessartine garnet – this is generally a yellowish orange species of garnet, although it can occur in the red range also. It’s slightly softer than Rhodolite at 7.25 on the Mohs scale but still with good toughness so it’s still not a stone to be too concerned with on the durability front
Tsavorite Garnet – is a bright green (which can rival that of emerald) grossular garnet. Generally ranging from yellowish green to bluish green, usually with much better clarity than emerald, and with a higher degree of toughness than emerald, it makes a much safer choice for a green ring stone! Like spessartine its hardness is 7.25 so for most jewellery this would be acceptable
Demantoid Garnet – this is the softest and least tough of all the garnets, so care has to be taken and consideration given to the kind of jewellery made with demantoid. It ranges in colour from yellowish green to green and usually contains what are known in the trade as horsetail inclusions. With a hardness of only 6.5 on the Mohs scale it is easily scratched and should not be used for every day rings.
Other garnet types include, hydrogrossular – a massive form of greenish to pinkish garnet, Malaya – an orange to reddish orange stone, melantite – usually so dark red it appears black, topazolite – a darkish yellow variety of the andradite species, uvarovite – a beautiful bright green garnet that mostly never grows in crystals bigger than druse and the colour change garnet which, as the name suggests, is a variety that changes colour depending on the type of light the stone is viewed under.
There are a huge range of colours in the garnet group and it’s definitely worth getting to know some of the different varieties, as it opens up many possibilities for alternatives to the more popular and well known gemstones.
The image above shows a large green tsavorite garnet, two purplish rhodolite garnets and one brownish almandine garnet.