Gemstones – Fact and Fiction….
It is indeed a fact that diamond is the hardest known substance to man. It also explains why diamond is such a suitable material to use in jewellery, particularly engagement rings which, by their nature, are worn daily and are often subjected to a fair amount of heavy handling! However, there are many other gemstones available – which ones are suitable for rings and which are better as pendants or earrings where they are less likely to suffer knocks and bumps?
Back in 1812, a German Mineralogist called Frederich Moh devised a scale of hardness of minerals. This scale does not increase in regimented steps, rather it is a guide from soft to hard: graded in ten increments with Talc (the softest on the list at 1) through to Diamond (the hardest at 10). The minerals he chose for the list were on the basis that most were readily available.
- Talc
- Gypsum
- Calcite
- Fluorite
- Apatite
- Orthoclase Feldspar
- Quartz
- Topaz
- Corundum
- Diamond
As we have already said, Diamond is the hardest known substance. This does not mean that it cannot be broken. A diamond posesses an ability to split along certain well defined crystal planes and this is called “Cleaving”. Diamond is very resistant to scratching (although it can be scratched by other diamonds so care should be taken when storing them. Diamonds are suitable for all types of jewellery from rings to pendants, bracelets, earrings, brooches and also used to accent watch bezels. There is a piece of jewellery set with diamonds for all occasions!
Other gemstones that are often used in rings worn everyday such as engagement rings are Sapphire and Ruby. These gems are both from the same family (Corundum) and when red, they are called RUBY and in any other colour, SAPPHIRE. People tend to think of Sapphire as being blue but it is available in a whole rainbow of colours. Pure Corundum is colourless and the colours of the Sapphires and Ruby are dependant upon various colouring elements in the chemical composition of the crystals when they formed millions of years ago. Again, all types of jewellery are suitable to contain these two gemstones.
Other gemstones often used in rings are from the Quartz family (frequently Amethyst and Citrine) and Topaz (golden, white, pink and blue). Although not as scratch resistant as Corundum and Diamond they are still fairly durable. They are gemtones popular in earrings, bracelets and pendants.
Emeralds and Aquamarines (from the Beryl family) are often seen in rings but they are more suitable as dress rings as they are a more brittle material and can be more easily damaged. They are an example of a gem that would be better suited to earrings, pendants and brooches as these items are less likley to be subjected to accidental bumps.
Gemstones whose hardness falls at about 6 and below on Mohs Scale of Hardness are much more easily scratched and set in pendants and earrings are more protected from possible damage than they would be in a ring.
When it comes to fiction, many people assume that the hardness of a gemstone means that it can’t be broken easily. If fact, the hardness according to Moh’s scale is the resistance to scratching, so a material with a hardness of, for example 7 on Moh’s scale would not be scratched by any material who has a hardness below 7 but materials possessing a hardness of 7 or higher would scratch it.
A more ‘fun’ side to the fiction is that of folklore regarding gemstones. Hopefully at some point in the future we will produce an article that covers some of these stories.
