A Gold IRA will likely be an positive diversification tool

https://temperance.blob.core.windows.net/financialupdates/GoldIRA/uncategorized/metals-ira-a-brief-report-on-physical-precious-metals-in-individual-retirement.html

A Gold IRA would be an fine diversification instrument, adding physical gold which may behave differently from shares for the duration of market downturns.