40th Wedding Anniversary Gift
Ruby – The red variety of the corundum family of gemstones. All other colours of corundum are termed Sapphire and, unless blue, the colour precedes the word Sapphire, so for example Yellow Sapphire, Green Sapphire.
Ruby is one of the traditional “big four” gemstones along with diamond, sapphire and emerald. It is a durable gemstone with a hardness of 9 on Moh’s scale of hardness. It should be noted however that the scale of hardness is how resistant to scratching the material is, not whether or not it can be broken.
Mohs’ scale of hardness is referred to in all of the gemstone articles on this website. The scale was devised by Frederich Mohs in 1822. It is a list of the relative hardness of minerals from 1, the softest through to 10 the hardest. There is, however, a greater difference in the degree of hardness between corundum at 9 and diamond at 10 than there is between talc at 1 and corundum.
The list reads:
1 – Talc
2 – Gypsum
3 – Calcite
4 – Fluorite
5 – Apatite
6 – Othoclase Feldspar
7 – Quartz
8 – Topaz
9 – Corundum
10 – Diamond
Ruby has become a gemstone associated with love and commitment and as such, it is a popular coloured gemstone for engagement and eternity rings; helped in part by it’s durability when worn in rings. However, despite this durability, we would always recommend that gem set jewellery is removed before undertaking any heavy manual work in order to avoid accidental damage.
Rubies are one of the rarest gemstones, especially in larger sizes and of good clarity. These factors greatly influence the price of this gemstone.
Historically many red gemstones were assumed to be ruby, including the famous Black Prince’s Ruby in the Imperial State crown of the United Kingdom’s Crown Jewels. It is in fact a completely different gemstone in its own right, a Spinel of an irregular shape, cut en cabochon (having a flat base and a domed top) and weighing 170 carats. It is set in the cross pattée above the Cullinan II diamond. There is more information about the stones cut from the cullinan diamond in our diamond article.
It is important to note that nearly all coloured gemstones, ruby included, will have undergone heat treatment to improve its colour. This is a practice that has been carried out for thousands of years; indeed, even in Roman times there was evidence of stones having undergone heat treatment. As it is a continuation of the natural formation of the gemstone it is an accepted treatment. It is also a permanent change.
Some rubies have a lead glass infilled into fissures within the stone to improve its clarity. This is a practice that MUST be disclosed, as any work done to a piece of jewellery containing such a stone could cause the filler to come out, leaving a very different looking stone to the one handed to the workshop, and a very unhappy owner of the jewellery.
If a ruby that appears to be of an extremely good colour and clarity and is for sale at a lower than expected price, questions need to be asked regarding treatments and also to make sure if it is a natural gemstone and not a synthetic one that has been produced in a laboratory.
We can make a ruby item to your specifications, however, please be aware that this can be a lengthy process so don’t leave it to the last minute if it is for a special occasion as the gem has to be sourced and often the mount will have to be handmade by our jeweller, a highly skilled craftsman who will work on the item for hours at a time. We are always pleased to be able to obtain a quote for a bespoke item.
Please see our other articles relating to other birthstones and anniversary stones:
Peridot – August Birthstone
Pearl – June Birthstone
Emerald – May Birthstone
Diamond – April Birthstone
Aquamarine – March Birthstone
