Source: Anvil of Fire, pg(s). 88
Magnetite golems are golems made from magnetite, a naturally magnetic mineral, and they emit a magnetic field which pulls metallic objects close. Because of this, they are hard to construct, cannot use metal tools, and constantly accumulate metal debris on their bodies, which their owners must regularly remove. They are also useful as guards, their magnetic pull removing hidden weapons or dragging intruders and their metallic gear toward them, in the process alerting other guards. Magnetite golems are usually about nine feet tall, and weigh approximately 1,500 pounds.