What do diamonds, windows and chalk all have in common?

They are all gauged by their strength on the “Moh’s Scale”, which gives a numerical value to each element based on its natural hardness and resistance to abrasion. Ranged between 1 and 10, the scale depends upon the area of indentation made in the material when it’s hit with a small steel ball (approximately 2mm in diameter). To give an example, we have started with No.1 being the softest natural element, Talc (Chalk), and finished wih No.10 — the hardest gemstone in the world, Diamonds.

Moh’s Scale of Hardness

1 Talc/Chalk

2 Amber; Soapstone; Bone; Fingernails

3 Calcite; Pearls; Coral

4 Cuprite; Rhodochrosite

5 Mesolite; Chromite; Window glass

6 Turquoise; Strontium; Marcasite; Steel knife

7 Quartz; Garnet; Tourmaline; Tanzanite; Emerald

8 Topaz; Chrysoberyl; Aquamarine

9 Sapphires; Ruby; and substances used as abrasives

10 Diamond

This list should be of particular interest to jewellery owners, as it emphasises the importance of looking after your diamonds, but especially for taking care of your softer gemstones. It is one of the main reasons Calleija offers a lifetime maintenance program with every purchase. As part of our guarantee agreement, all we ask is that you bring your Calleija jewellery in for its complimentary clean and check every six months (and once in the first three months), to ensure your jewellery will be long lasting and treasured for generations to come.