Dimeritium Ore
Dimeritium is the metal that dampens magic, and in The Witcher 3 its raw ore sits near the top of the crafting chain. Most witchers want it for one reason: the grandmaster versions of the school gear added in Blood and Wine.
Where to get it: Random loot throughout the game, guaranteed loot in many bandit camps, guarded treasures and treasure hunts in Toussaint, a few merchants, or dismantling dwarven and gnomish swords and higher-tier witcher gear.
Crafting: The Refined dimeritium ore diagram turns 1 × dark steel ingot and 1 × meteorite silver ingot into ore.
Used to craft: Dimeritium ingot and enriched dimeritium ore, which you need on the way to grandmaster witcher gear.
Get it by dismantling: Grandmaster Feline Gauntlets, Grandmaster Ursine Gauntlets.
How to obtain
Sold by: merchants in Skellige, the Grandmaster smith in Toussaint and the Ofieri merchant (Hearts of Stone).
Keep exploring
Plan a Remastered build: skill trees, mutagens, gear and a shareable build image.
Pick a potion, decoction or bomb and see every ingredient you need.
Answer the key choices and find out which Witcher 3 ending you will get.
Every location, quest and monster in the first region on one map.
The Wolf School's hidden valley: the keep, the Bastion, caves and treasure.
Tick off every school gear diagram and crafted piece, with diagram locations.
Search any monster and see the right oil, Signs and bombs.