Credits: 4cs.gia.edu
Engagement rings with a colored center gem are making a huge comeback and have been gracing the hands of celebrities and royalties for years.
As you know, diamond is the hardest gem in the world, but what about the hardness of all other precious gems?
This is an interesting question because most people want to wear their ring every day, so in order to avoid unpleasant damages, it is good to know the degree of hardness of the gemstone your ring is made of.
So, let me introduce you to the Mohs scale.
This scale, presented in 1822 by Friedrich Mohs – from which it takes its name – is used to evaluate the hardness of minerals.
What do we mean by hardness?
Hardness is the ability of a mineral to resist scratches and sharp points.
The concept of toughness is different, as it means the ability of a mineral to resist breakage, cracks or chipping.
Dr. Mohs assigned values to ten minerals, based on the ability of each gem to scratch another, making the scale in use still today.
Please note that the Mohs scale is not linear and the position occupied by a mineral does not clarify how much this mineral is harder and tougher if compared to the mineral following in the scale. For example, although diamond and corundum (i.e. sapphires and rubies) are separated only by one position, diamond is many times harder than corundum and corundum is twice as hard than topaz.
Therefore only a diamond, which sits in the first position of the scale, can scratch another diamond.
Corundum can scratch another corundum and also a topaz, a quartz and any other more delicate mineral that follows in the scale, but cannot scratch a diamond.
The Mohs scale helps to identify which gem is more suitable for frequent use, but it is also useful to choose the type of jewel. For example, the alluring tanzanite straddles the 6 – 7 position on the Mohs scale. Low in hardness and with a propensity to crack if struck, tanzanite is therefore perfect for jewels that are less exposed to accidental blows, such as earrings and necklaces. However, if you are very much in love with tanzanite and want your ring to be surmounted by this wonderful gemstone, thanks to the Mohs scale now you know that it is a delicate stone and that you must wear your ring with precautions and, possibly, reserving it for special occasions.
A good way to save a delicate gem is to choose a suitable setting, which protects it from the risk of chipping or breaking (such as a bezel) and also to have the setting checked regularly by your trusted jeweler.
As a last suggestion, I remind you not to place a diamond in the same box together with another and more delicate gemstone because the former could scratch the latter. Try to keep the various gemstones in separate boxes (or compartments).
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