Gold Stocks for Retirement: iShares Gold Trust (IAU) Let's face facts, buying physical bullion can be difficult and costly for the average investor. Having physical gold bars in a safe is useless if you're not looking to protect yourself from the next zombie apocalypse and are just looking for inflation/downside protection, The iShares Gold Trust(ETF) (NYSEARCA: IAU ), is far from useless for those retirement investors, however. IAU is what's known as a physically backed exchange-traded fund.