The MOHS Hardness Scale is universally used as a way of distinguishing minerals, starting with talc at 1, being the softest mineral and ending with diamond at 10 being the hardest mineral.

It’s a pretty durable gem, too, with a tourmaline hardness of 7 to 7.5 on a scale. This means it can handle being worn a lot. Because it’s not common and looks so great, it’s considered one ...