GEMS
Gems are a random drop from Mining. When you mine any Ore, you have a chance to find a Gem.
There are currently 4 In-game Gems, the Sapphire 
Emerald 
Ruby 
And Diamond .
You can Cut these Gems with Crafting 
, Enchant the Cut forms with Enchanting 
, and Craft a Necklace using Forging 
.
You can Also Use gems in Forging a Treasure Chest Key, which is Used to Obtain More Rolls when Opening A Treasure Chest.
You can also Use the Gem Necklace, which will give you a 15% boost of finding gems when mining Mini Ore Nodes. 