Gem

Gems are items that can be embedded into specific gear to provide bonuses. Gems can be won in-game through some quests, as well as purchased from the Marketplace.

You can use Socketing Stones to add gem sockets to gear. You can use Gem Embed Charms to attach Gems to gear with sockets. Extract Stones allow you to remove Gems from gear. All of these items can be purchased from the Marketplace.

Gems can be combined with each other to create a higher level gem. Doing so requires a Gem Combination Charm purchased from the Curiosity Merchant in Luo Yang, in addition to the five gems you want to combine.

If you have extra gems (level 3 or lower) of the wrong type, you can sell them to a NPC to get Gem Shards. These can be exchanged with Flawless Yuu in Luo Yang for new gems. You will not get Gem Shards for selling level 4 gems or higher.

Flawless Yuu will also allow you to bind your gems. There is a small chance when binding your gems that you'll receive an extra gem of the same type.