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Is a diamond a gem or a mineral?

What makes a diamond so special? Why are diamonds a go-to for jewellery makers? What makes diamond jewellery so alluring and popular amongst buyers? The answer to all of these questions and more lies within the answer to if a diamond is a gem or a mineral. The explanation is interesting and worth delving into.



Let’s first find out if a diamond is a mineral. To be defined as a mineral, a substance must meet five specific requirements.

  1. A mineral is naturally occurring. This means that a mineral creates itself naturally and is not made by humans. Diamonds do indeed exist in nature without the aid of the human hand. They form at about 100 miles deep in the Earth’s mantle where the high temperatures and pressures necessary to form diamonds can be reached.
  2. A mineral is inorganic. In order for something to be inorganic, it cannot be made by a living organism. For example, pearls are formed by oysters when foreign objects or parasites get lodged into their shells. Since oysters are living organisms, pearls are not inorganic. Diamonds, on the other hand, are formed in the Earth through chemical reactions with no organisms involved, making them inorganic.
  3. A mineral is solid. Ok, so a lot of things are solid. But this means that the substance in question must not be a liquid or a gas at standard temperature and pressure. Diamonds are very solid at temperatures and pressures that people can withstand.
  4. A mineral has a definite chemical composition. This means that every occurrence of the substance has the same chemical composition and that it is uniform throughout each occurrence. Diamonds are made entirely of carbon so they easily fall into this category.
  5. A mineral has an ordered internal structure. The elements that make up a mineral are always in a fixed systematic and repeating structure. This helps to cause the rigid solid structure of minerals, diamonds included.

Diamonds meet the five requirements of a mineral!



So is a diamond a gem? A gem is simply a hard substance, commonly a mineral, which has been cut and polished. Thus, yes, a diamond is a gem! Carat (a weight measurement), cut (quality of workmanship), colour (completely colourless are the most expensive, but coloured diamonds are becoming increasingly popular), and clarity (free from impurities) are used to value diamonds and other gems.

The hardness of diamonds makes them very suitable gemstones. A diamond can only be scratched by another diamond; this scratch resistance makes them popular for everyday wear.

Diamonds also have a high lustre value; this is just the term for the light reflection that causes that famous diamond sparkle. Diamonds also possess the ability to disperse white light into beautiful rainbow colours, which adds to its value as a gemstone.


Both mineral and gem, diamonds are renowned for their versatility, durability, beauty and quality. They are the world’s most popular gemstone, and perhaps mineral as well. Long answer short, a diamond is first a mineral, then a gem.

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