"It grows like roots in the ground. Something about this material is strange. It appears to be sentient and able to know what happens in it's surroundings." ~From the personal notes of a researcher.
When the people dug into the ground for the riches they provide, they found gems, iron and what is known as Tharisium. This ore is of strange properties, able to store arcane energies like a living being, while showing no signs of life or sentience. The material is very durable in pure forms, easily melted down and just as simple to be smithed. Weapons with a Tharisium alloy are able to channel spells inside of them, ready to be discharged at will.
According to the mining clans that provide large masses of this ore call it a rarity like no other, despite the fact that the statistics about the trading and logistics of Tharisium indicate that the material is in much larger quantities on the market than good quality steel or rare gems such as ruby or emerald.
For a Magician or Magi that dwell on the crafting and creation of Foci, Tharisium is a component known to be of great use, especially in the production of Foci and Charms that are made out of metal. In many cases, Foci receive a much larger spike in strength through Tharisium.