Ever heard the old trick question, "which weighs more a pound of feathers or a pound of gold?"
The answer is supposed to be neither, because both would be a pound, yet that answer is technically incorrect.
Gold is universally weighed using a different measurement system than most other materials. It is weighed using the troy system, and troy ounces.
This system is measured so that 12 troy ounces makes up 5760 grains to the pound, while the common measurement for feathers would make them equal to 7000 grains to the pound.
Thus, a standard pound of feathers technically weighs more than a pound of gold!