This rare metal combines the weight of lead with the strength of steel. Orcs prize it for weapons because the extra weight allows a skilled user to strike with more force. Thorium armor is amazingly heavy and strong — only adamantite pierces it with any degree of reliability. Thorium is heavier than most metals. An item made from thorium weighs twice as much as the same item made from other metals.
Small Thorium Veins and Ooze Covered Thorium Veins require mining skill 230, Rich Thorium Veins and Rich Ooze Covered Thorium Vein require mining skill 255.
The Thorium Brotherhood faction drew its name from the metal, as well.
Items mined from Thorium Veins:
Patch 1.3.0 (07-Mar-2005): Drop rates of very high-end gems have been somewhat increased on rich thorium veins.