 Complete the following phrase:  A French law of 1803 granted anyone who brought gold or silver to its mint the right to have it coined at a nominal charge in addition to the official rates of 200 francs per kilogram of 90 silver, or 3100 francs per kilogram of 90 fine gold. This effectively established a bimetallic standard at the rate which had been used for French coinage since 1785, i.e. a relative valuation of gold to silver of 15.5 to 1. In 1803 this ratio was close to the market rate, but for most of the next half century the market rate was above 15.5 to 1. As a consequence, silver powered the French economy and gold was exported. Then the 