Spinel
‘Spinels’ are a gemstone that are part of a larger mineral family, also named spinel. In the past, red spinels have been confused with rubies, to such an extent, that both rubies and spinels were called ‘spinel rubies’. It is only with modern scientific techniques that we have been able to separate the two. What we today define as rubies are the red variety of the mineral corundum, whereas spinels are, well, spinels.
When this differentiation was first recognised and appraisers and valuers began to identify gemstones previously thought to be rubies as spinels (a gemstone few had heard of) the reputation of spinels suffered. These days, although not as widely known as rubies, spinels are a sought after and recognised gemstone in their own right.
The confusion comes because of the similarities of the colour. Although spinels can be a few different colours, they can sometimes be a deep red colour like high-quality rubies. These stones are famous for their intense red, orange, and pink colours which set them apart from other spinels.
As well as red, spinels come in black, purple, grey, pink, orange, and blue. All these colours of spinels are used in jewellery and their values differ according to their rarity.
A blue spinel crystal
Red Spinel crystals
How hard are Spinels?
Spinels measure 7.5 -8 on the Mohs scale of mineral hardness, a scale that goes from 1-10, and measures a mineral’s resistance to being scratched. This rating means that spinels are suitable to be worn in all types of jewellery, however, if they are worn continuously in items like bracelets and rings, which are more likely to get bumped and knocked, then they will show signs of wear.
Where are Spinels found?
Spinels are found in many locations around the world and in different types of rock. In Sri Lanka, they are found in secondary gravel deposits and in Afghanistan, Tajikistan, and Myanmar they have been found in limestone. Tanzania is an important source of spinels and specifically the area around the village or Mahenge.
Mahenge Spinel
There have been many famous Spinel finds over the years. One of the most intriguing was the discovery in 2007, of a huge spinel crystal in Mahenge, Tanzania. Nothing of this sort had been found in the region before and the stone, which weighed 52kg, approximately 260,000cts, was cut into many-faceted gemstones. As these stones percolated through the world market, Mahenge Spinel became a stone known to jewellery and gemstone collectors all over the world.
Purple Spinels from Tanzania and Sri Lanka
References&Permissions
As well as our own experience of visiting Tanzania, mindat.org , gia.edu and ethical gemstone mining company Nineteen48 where the main sources for this article.
All images are intellectual property of Edward Fleming jewellery and must not be used or reproduced without permission. If you would like to use content from this article please feel free, however all content used must be credited and linked too, unless express written consent is given. Any unauthorised use of content will be prosecuted.