Some historians believe the real golden plates were also made from an alloy that included gold. A block of solid gold the size of the golden plates would weigh about 200 pounds (90 kg), but the weight of the gold plates, as estimated by the few people who lifted them, was somewhere between 40 and 60 pounds (18 and 27 kg). An alloy of gold and another lighter metal and the air pockets between the plates could account for this difference in weight, say some historians.