Brief context to the TL;DR topic of Gems, written for new players
You want DMG, CD, CH on your gems with no boosts to CHTop ^
Why is this? You may eventually reach 100% chance to critically hit without the help of those small blue icons people call 'boosts' you can only see when you use the Gem Forge. Some Classes get Critical Hit% as they level, but most will require level 25 [stellar] gems.
Just How Imporant Are Boosts?Top ^
Well, to get all three boost icons, your gems must start with three stats on them. However three stats is only about half the picture when it comes to gems, gem levels 5, 10, and 15 each apply a boost randomly to one of the stats. 43.8% of the total gems damage potential is from boosts. A Chaos Flare can remove a single boost from one selected stat, with a 50/50 chance of placing it between the other two. Flares can become important later when you want to balance your DMG&CD boosts.
Don't Know If You Should Keep Gems With Low%?Top ^
Relatively speaking, if your boosts are in the right place... going from 0% to 100% with gem augments is only 25% of the gems total damage potential, so if you had a fast rule like 'lesser stellar gems must be >1250 PR' (>62% avg), they would only be missing 9.5% of the gems total damage potential. 25%? 9.5%? vs 43.8%? boosts are very important!
What Else Before Augmenting Gems?Top ^
Unboxed Lesser Gems will have a Fierce or Arcane prefix, that limits the gem to only Physical or Magic damage. Empowered Gems can swap from Physical to Magic because they're so
RNG difficult to acquire. After gem level 15 use Luckbugs, then at 23 switch to Ninth Lifes to reach level 25. Check out Boost Combinations, the difference between the worst combination and the best is around 15%.