Deepgold
From Wulfgard Wiki
Deepgold is a rare metal only found deep within the earth. It is almost exclusively mined by dwarves. As its name implies, it is gold in color, but unlike ordinary gold, it is extremely durable and can be forged into highly effective armor and weapons. However, it is no lighter than an ordinary metal. Deepgold is incredibly expensive due to its rarity, luster, and usefulness combined. Only very rich individuals or organizations, such as the Knights Templar, can afford deepgold.