3.21.2c Patch Notes: Geodes, Remnants and Magmatic Ores will be deleted upon logging in.
Magmatic Ore
Magmatic Ore adds stored Crucible experience to an item. The minimum Stored Experience is 40000. The maximum Stored Experience is larger than 2092194.
How to use it?
Right click this item then left click an item with a Crucible Passive Skill Tree to apply it.
3.21.0b Patch Notes: Increased the amount of Crucible Passive Skill Tree experience gained from encounters, particularly for encounters that are not fully-channelled. This should result in smoother progression on the experience bar while channelling.
How to get it?
Crucible Passive: Item sells for an additional Magmatic Ore. (Search)
Drops in the Forge of the Titans. Primeval Remnants mods: Rare and Unique Monsters have 25% chance to drop a Magmatic Ore. (Search). Primeval Remnants always generate as rare items. Half of their mods are upsides and half are downsides. The upsides generally increase the rewards of the area or add special crafting options. For example, causing monsters to drop Divination Cards or Magmatic Ore, a form of tradeable itemised Crucible tree experience. The downsides are quite punitive compared to most in-game maps. Ideally, you want to find a primeval remnant that has really rewarding upsides alongside downsides you can handle.