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What is the Mohs Hardness Scale and why is it important...?

Have you ever been faced with the comment, "This stone has a Mohs hardness of 6.0"? You look at the sales clerk, smile and nod, having no clue what he just said!

Well I am here to help you with some of the inside lingo of the Jewelry Industry.

What is the Mohs Hardness Scale?

The Mohs Hardness Scale, developed by Friedrich Mohs in 1812, is a system used to measure the relative hardness of minerals and gemstones. It assigns a value from 1 to 10 to each mineral, with 1 being the softest and 10 being the hardest. This scale ranks minerals based on their ability to scratch or be scratched by other minerals.

A gem with a Mohs hardness of 8 will scratch a gem with the hardness of a 6. The Diamond, with a Mohs hardness of 10, will scratch most any other gem. Talc, with a Mohs Hardness of 1, can be scratched with your fingernail.

Importance of the Mohs Hardness Scale in jewelry.

The Mohs Hardness Scale helps determine the suitability of gemstones for specific jewelry pieces. Gemstones with a higher hardness value are more resistant to scratches, making them suitable for everyday wear, while softer gemstones may be more prone to damage.

Understanding the durability of different gemstones, you, the consumer, can make an informed decision about a piece of jewelry. Do I wear my Opal Necklace to the beach? Probably not. Will my diamond engagement ring be beautiful for years to come? Probably.

Knowing this information before buying high end jewelry with gemstones is invaluable.

Common Gemstones and Their Mohs Hardness Ratings

Let's explore some popular gemstones and their corresponding Mohs Hardness ratings:

a) Opal (Mohs Hardness 5.5-6.5): Opals are delicate gemstones with a lower hardness level and are made up of small spheres of silica gel. They require special care to avoid damage and are better suited for occasional wear.

b) Amethyst (Mohs Hardness 7): Amethyst, a variety of quartz, has a moderate hardness and is suitable for various types of jewelry. However, care must be taken to avoid harsh impacts and chemicals.

c) Topaz (Mohs Hardness 8): Topaz is a popular gemstone known for its vibrant colors. While it is relatively hard, caution is still necessary to prevent scratching or chipping.

d) Sapphire and Ruby (Mohs Hardness 9): Both sapphires and rubies belong to the corundum mineral family, making them highly scratch-resistant and perfect for daily wear.

e) Diamond (Mohs Hardness 10): As the hardest mineral on the scale, diamonds are the ideal choice for engagement rings and other jewelry that requires long-lasting durability. Remember from the April Birthstone Blog, the Diamond is highly prized when cut perfectly and has no flaws. However, is very common and is even used on some of the files in my workshop because it will cut anything!

Understanding Gemstone Combinations

The Mohs Hardness Scale is especially crucial when designing jewelry with multiple gemstones. It helps prevent one stone from scratching another. Generally, gemstones within one or two hardness levels of each other can be safely combined in a design.

By considering a gemstone's hardness, creators can ensure the durability and longevity of your jewelry pieces. Also, consumers can decide if a piece of jewelry will be suitable for their lifestyle.

Whether it's a diamond engagement ring or a delicate opal pendant, understanding the Mohs Hardness Scale is an invaluable tool for consumers. So the next time the sales clerk makes the statement, "This stone has a Mohs Harness of 9." You will understand that the stone is tough durable and probably a beautiful Topaz!

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