While diamond is the hardest gemstone, its all-round durability is considered less than that of relatively softer gemstones, such as sapphires and rubies, which can garner higher prices due to their toughness.

Any gemstone that, is approximately the hardness of quartz (7) is said to be 7 in hardness, but if it tests between two of the minerals on the scale, it is expressed by 1/2. Thus a gemstone that tests harder than quartz but softer than topaz is said to be 7 1/2 in hardness.

Sep 11, - Sapphire is one of the four recognized precious gemstones and the second hardest mineral on earth after diamond. This deep blue gemstone has 

Let’s have a look at the hardness of different gemstones! It would be hard to gauge actually how hard a gemstone is simply based on the relative numbers on the Mohs Scale. Here are the Mohs hardness levels of various daily objects to give you a better picture: Masonry drill bit (for drilling tiles and concrete) 8.5 - 9. Steel nail 6.5. Glass 5.5.

The diamond is the hardest gemstones, while talc is a very soft mineral. The scale by which the hardness of minerals is measured is the Mohs Hardness Scale.

9/28 · Here are a few of the rarest from around the world. 1. TANZANITE // FOUND ONLY IN TANZANIA. GeologMax via Wikimedia // CC BY-SA 4.0. Tanzanite is a beautiful blue variety of the mineral zoisite

8/15 · 10. Gypsum. Gypsum found in Poland. Mohs hardness: 2. Absolute hardness: 3. Chemical formula: CaSO 4 ·2H 2 O. Gypsum is a sulfate mineral composed of calcium sulfate

It is the most complete and accurate hardness scale for gemstones available online, and includes many rare varieties. Click on a gem link to see examples or find more information. Diamond. 10. Ruby. 9. Star Ruby. 9. Sapphire.

7/25 · This is why it is the hardest substance on earth. Naturally, graphite is the most stable form of carbon. However, it converts to diamond under high temperature and pressure. According to Professor David Phillips, diamond is usually 99.7 percent carbon. The remainder consists of impurities of other elements that impart diamond its colors.

The 180-carat opal is especially admired due to its large size and intense harlequin coloration; in 2005 it was valued at AUS $1,000,000, or about $763,000 U.S. 3. LARIMAR // ONLY FOUND IN THE

While diamond is the hardest gemstone, its all-round durability is considered less than that of relatively softer gemstones, such as sapphires