Bullion is gold and silver that is officially recognised as being at least 99.5% pure and is in the form of bars or ingots. An investor who wants to purchase precious metals can purchase it in physical bullion form or paper form. Investing in gold through exchange-traded funds (ETFs) is not equivalent to owning gold. Instead, gold is owed to the investor. With gold and silver futures contracts, the seller is committing to deliver gold to the buyer at the contract expiry date. Until the delivery happens, the buyer will not own the gold, and will only be an owner of a paper gold contract. However, if the buyer does not want to own gold bars or coins, he can sell the contract before the expiry date or roll the contract over to a new one. With Gold or Silver ETFs, the underlying asset might be gold certificates or silver certificates, and not the physical bullion itself. Gold certificates can be exchanged for the physical gold or for the cash equivalent at a bullion bank.