Once a gem is placed into a socket, it cannot be removed or restored.
Sometimes my Soulfire Chisel won't remove a gem
What to do if you're unable to conjure a mana gem.
Information on an issue where a socketed gem is not providing its bonus.
Purchased Heroes of the Storm Gems for the Wrong Region
Information about unique-equip errors when attempting to equip a socketed item
What to do when all cards on a Hearthstone pack are common quality
Why a crafted Legendary in 9.1 may not have a gem socket in it.
Troubleshooting lost items in the stash.
What to do if your helmet, chest, and shoulder armor appear invisible without transmogging them as "hidden".