The MOHS Scale Explained: What does this mean for your everyday jewellery?
When choosing jewellery, beauty is only part of the consideration. Understanding how a gemstone responds to everyday wear can help you select a piece that suits both your style and lifestyle.
One of the most widely used guides to gemstone haldness is the Mohs Scale.
What is the Mohs Scale?
In 1812 Friedrich Mohs, a German geologist developed the Mohs Scale. It arranges minerals from 1 to 10 according to their resistance to scratching.
At the lowest end of the scale is talc, rated 1, while diamond sits at the top with a rating of 10. It is important to remember that the Mohs Scale measures scratch reistance only. It does not measure a gemstones overall strength, toughness or liklihood of chipping and breaking. A gemstone may resist scratches exceptionally well while still being vulnerable to a sharp impact.
The scale is also comparative rather than perfectly even. Diamond is not simply twice as hard as a mineral rated 5, it is significantly harder.
Which Gemstones Are Best for Everyday Wear?
Many of the gemstones most commonly chosen for engagement rings and everyday jewellery sit between 7 and 10 on the Mohs Scale.
Diamond - 10
Diamond is the hardest naturally occuring material and offers execptional resistance to scratching. This makes it particularly well suited to engagement rings and other pieces worn everyday.
However, hardness does not make a diamond indestructible. A forceful impact, particularly along a vulnerable edge or point, may still cause it to chip.
Sapphire and Ruby - 9
Sapphire and ruby are both vareities of the mineral corundum and rate 9 on the Mohs Scale. Their excellent scratch resistance makes them beautiful and practical choices for everyday jewellery.
While still requiring thoughtful care, sapphires, rubies and diamonds are generally among the most suitable gemstones for frequently worn rings.
Emerald - 7.5 to 8
Emeralds rate approximately 7.5 to 8, meaning they resist scratches from many materials encountered in daily life. However, they often contain natural inclusions that can make them more vulnerable to chipping or breaking. These inclusions are part of an emeralds natural character and are sometimes described as its jardin, meaning "garden" in French. Emerald jewellery can certainly be worn and enjoyed with a more delicate approach and should be protected from impacts and sudden tempreture changes.
Amethyst and Citrine - 7
Amethyst and citrine are both varieties of quartz and rate 7 on the Mohs Scale. They offer reasonable scratch resistance, although they still require care when worn regularly. Prolonged exposure to strong sunlight may cause their colour to fade over time. Sudden tempreture changes can also place stress on the gemstone and increase the risk of damage. To preserve their colour and clarity, store these pieces away from direct sunlight and avoid exposing them to extreme heat.
Opal - Approximately 5.5 to 6.5
Opals are treasured for their mesmerising play of colour, but they are considerably softer than diamonds, sapphires and rubies. With a rating of approximately 5.5 to 6.5, opals are more susceptible to scratches and everyday damage. They may also be sensitive to impact, heat and sudden tempreture changes. Opal rings are best worn thoughtfully, while earrings and pendants offer a more protected way to enjoy this distinctive gemstone.
Hardness is Only Part of the Story
A higher Mohs rating can make a gemstone more suitable for regular wear, but it does not tell us everything about its durability. When selecting a gemstone, it is also important to consider:
- Its resistance to chipping and breaking.
- The presence of natural inclusions.
- Its setting and how well the stone is protected.
- How frequently the jewellery will be worn.
- The wearer's lifestyle and daily activities.
Even the hardest gemstones should be removed before excercising, gardening, cleaning or completing hands-on work.
Choosing the Right Gemstone for You
The Mohs Scale is a helpful stating point, bbut choosing a gemstone should never be based on hardness alone. Some softer stones may require additional care, yet their beauty and individuality can make them wonderfully meanigful choices.