Talk:Garnet/@comment-27092450-20160109021351/@comment-24939728-20160110164925

There's this entire theory that the Mohs Hardness Scale represents the gem hierarchy; for example, since Diamond is a 10 and is the hardest known mineral on Earth, gems like Blue Diamond and Yellow Diamond (as well as the other Diamonds) are at the top. Pearls, for example, can range from a 2 to 4. All varieties of Quartz are a 7 on the scale.

Also they stated that in fusions, if two gems of the same hardness fused (Ruby and Sapphire = 9) they would make a gem of a lower number (Garnet: 7). If the gems don't have the same hardness (Pearl: 2-4 and Amethyst: 7), the fusion would result in a hardness somewhere in the middle (Opal: 5).