There are many ways to invest and trade in gold and other precious metals, and the choice you make impacts the way you input and track your investment on Exirio.
If you invest directly in the physical metal, which means owning and storing the actual bars or coins, you add it by choosing Precious Metals as Asset Class.
Otherwise, you can invest in through a mutual fund or an exchange traded fund. This is an indirect form of investment, where investors place their assets into a fund and in turn the fund invests in metal. With an exchange-traded fund, equity in the fund is traded on a stock exchange, therefore on Exirio you add it as an ETF (Funds & Public Securities Asset Class).