Gems and Their Hardness Rating

When you visit Davidson & Co, you will find an informative staff knowledgeable about the type of gemstones we offer and their characteristics. The "hardness rating" of a gemstone is very important and has an effect when creating jewelry, especially rings. The durability of a gemstone is important. For example, some rings, like wedding rings, are worn every day. This makes them vulnerable to thumps and knocks that can be hazardous to a gemstone. Some gemstones are stout enough to be placed in a ring that can be worn day-to-day, other gems are best for rings worn on an infrequent basis, and there are some gems that are not fit to be used in rings at all! 

Gems and their Hardness Rating

One vital factor in measuring gemstone resilience is hardness. In gemology, a stone's hardness is gauged on a scale called the Mohs Scale, which allocates minerals a hardness rating between 1 for the softest and 10 for the hardest stones. The Mohs Scale was created in 1822, by a German mineralogist named Frederick Mohs. It characterizes hardness depending on the gem's scratch-resistance, in which a harder stone will scrape a malleable one, but not in reverse. 

Diamonds are rated the hardest with 10, sapphires and rubies follow with 9, spinel, emerald, and topaz 8, quartz, tourmaline, and garnet 7. The supplest stones are talc-1, gympsum-2, calcite-3, and fluorite-4. The margin between harder and softer gemstones is usually given a Mohs rating of 7. Gems with a solidity of 7 or higher is best for rings, hardness ratings below 7 are not. 

Is the Moh's System still Relevant Today?

The Moh's system, which determines the hardness rating of a gemstone, is somewhat simplistic in the eyes of today's gemologist. For instance, for a wedding or engagement ring intended to be worn everyday a hardness rating of 8 to 10 is advised. However, other factors are relevant as well. Take emeralds, they are characteristically heavy with various minute interior fractures. Therefore, in spite of its hardness rating of 8, emeralds are not considered tough enough for daily wear.

Moreover, Mohs scale is a "relative-scale" not an absolute one. It only demonstrates which gem is harder than another one, a comparative concept. Prior to any scientific equipment being used to examine minerals optically, mineralogists relied unswervingly on the Mohs Scale scratch-test much more than they do today. At present, with more advanced technology, the scratch assessment method for hardness is hardly utilized because of its vague testing of hardness and the likelihood of impairing the specimen being tested. 

At Davidson & Co, we use the latest and best hardness rating methods to determine the strength of any of the gemstones we offer. This way, we ensure that our customers are satisfied with their jewelry purchase.

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