When Pokémon Go adds new mechanics to the game, they typically come with several pieces that play into each other. For Shadow Raids, this means the combined usage of Shadow Shards and the Shard Refiner to make Purified Gems.
Shadow Shards are new items that drop when completing certain tasks in Pokémon Go, such as defeating members of Team Go Rocket and completing Shadow Raids. Though I have seen the most success with Shadow Raids, which appear to give more Shadow Shards than typical Rocket encounters.
Once players collect Shadow Shards, they can use Professor Willow’s Shard Refiner to create Purified Gems, which can then be used during Shadow Raids as a way to make them easier once the raid boss becomes enraged.
Related: What are Shadow Raids in Pokémon Go and how do they work?
How to use the Shard Refiner to get Purified Gems in Pokémon Go
The Shard Refiner is just the name for Pokémon Go’s mechanic to turn one item into another. Players won’t actually need to use them at all.
Once you collect four Shadow Shards, a prompt will appear thanks to Professor Willow. He will use the refiner and automatically turn them into a Purified Gem. This will all be done in a small cutscene before depositing the newly crafted item into your bag.
This will happen every time you collect four Shadow Shards, though you can only hold 10 Purified Gems at one time. You can use these gems during Shadow Raids to turn the tides in your favor by lowering the offensive and defensive stats of the raid boss for yourself and your teammates.
