Thaumium

Thaumium is a magical metal created using a crucible with eight Metallum and four Praecantatio. Ingots are used to make a variety of thaumium weapons, as well as special types of magic blocks, such as Arcane Stone Blocks.

Think of it as a base magic metal used to make other magic devices.

Before it can be crafted, the player must first researchBasic Transmutation, and then Thaumium. (See research details)

Here's a video about Thaumium:

Thaumcraft 3 Tutorial, Thaumium

Uses

Thaumium is used in the crafting of the following items:

• Armour
  • Thaumium Helmet
  • Thaumium Chestplate
  • Thaumium Leggings
  • Thaumium Boots,
• Instruments
  • Thaumium Pickaxe
  • Thaumium Sword
  • Thaumium Shovel
  • Thaumium Axe
  • Thaumium Hoe
  • Thaumium Scoop
  • Thaumium Grafter
• Blocks
  • Magical Building Blocks

Research Details

Thaumium
Permutatio
Metallum
Praecantatio

Crafting

To craft Thaumium requires eight Metallum and four Praecantatio in a crucible, along with five vis.

To Research this you need Metalum, Praecantio, and Permutatio.