Embedding is this game's version of attaching a buff to your weapons/armor. The higher star rating weapons have more slots to embed.
To embed a jewel:
- Head over to the Blacksmith at Mt. Tianzhushan (Unlocked after completing the 4th story mission)
- Choose Embedment and pick then any equipment piece.
- Now you'll need to pick “Choose embedding slot” and pick one of the buffs that you want to remove, then confirm. (This is done to free up a embedding slot.)
- Now select “Choose embedding slot” once again and the question-marked slot to open a list of all possible special effects you can embed.
- Pick any of these effects and confirm
As a sidenote: Embedding costs Jewel Fragments and a decent chunk of currency (Copper). Jewel Fragments can be found in missions but imo it makes more sense to just salvage some from trash equipment that you've found (This can be done at the Blacksmith in the Hub World too). This is especially helpful later in the game as it lets you really customize the buffs you get out of your armor and weapons so I would recommend scrapping whenever possible. Copper is gained from killing enemies and selling equipment; selling equipment does NOT require you to be at the blacksmith.