You are partially right, but silver is a lot easier to use for coins then Gold. Gold is like a large saving bond which preserves the buying power, sort of like interest on bonds. Gold can be broken down into smaller coins but the cost of conversion can cost you big time. If you go buy a car and pay in 10 one ozce coins no problem, Go to the store and buy $100.00 worth of stuff for 3 oz of silver is possible.
Basically both Gold and Silver are needed for exchange as coins. Industrial demand for silver will increase as solar cells are made to offset energy costs in the future.
Gold and Siver shares will always be in demand as the shareholder own the gold and silver in the ground.