Gold too, has industrial uses, but it is minuscule compared to the supply of gold and also the uses for silver.
Possibly the best for doing all of such things is gold. Since 2001, the gold bull run started and it has not stopped yet.

Put in with investing in gold is generally there is any imbalance in this supply and demand is actually not enormous.
More adventurous s can simply invest in African companies. You need to spend a while to find out gold exactly what it can do for your business.