Broken Crown in Vault

Probably known by most players, but anyway, especially in season where you need lots of gems for augmenting and rerolling rings and amulets it’s a good idea to try and use the Broken Crown (best in Cube so you don’t lose your set bonus) to get double amount of the gem type worn in your helmet.

You can also use the Broken Crown effect when opening resplendent chests (maybe have the Crown in inventory a do a quick swap before and after opening).
If you get too many diamonds Squirt sells a recipe for the cube that can convert gems. Just remember that it takes 9 gems of the same value.