In 1851 the value of gold produced was one and one-half times that of silver; in 1852 was three times, and in 1853 four times as great; and then slowly declined, but continued every year as late as 1870 to be over twice as great.
This caused the displacement of silver by gold and drove out a large proportion of the silver coins of smaller denominations.

This led to the law of 1853, authorizing subsidiary coinage (on government account only) of lighter weight.[2] Let us observe the effect on prices that was brought about by the discoveries of 1848-49, and, first, we must consider briefly the method of measuring and expressing general changes in prices.
Sec.3.

#Concept of the general price level.# The price of any good is some other good or group of goods given for it in trade.[3] The standard unit of money coming to be the most convenient expression for price (whether or not money be actually passed from hand to hand in that particular trade), prices usually are monetary prices, and more specifically are prices in gold, or in silver, or in whatever constitutes the standard money unit.

But the price of each good is a definite, separate fact, which expresses the ratio at which that commodity is sold.

The price of any particular kind of goods may fluctuate in either direction as compared with the prices of other goods at the same time.