what is the background behind creating this act?
The Coinage Act of 1792 established the Mint of the United States, and made both gold and silver legal tender.
Coinage Act of 1965
The Coinage Act of 1792 established the Mint of the United States, and made both gold and silver legal tender. This meant that anyone could present bullion at the Philadelphia Mint and receive it back, struck into coins. The 1792 act authorized six silver coins, in value from five cents to a dollar, and prescribed their weights and fineness. 
what is the coinage act of 1965? It eliminated silver from the circulating United States dime (ten-cent piece) and quarter dollar coins.
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Coinage Act of 1965 [SEP] Background
The Coinage Act of 1792 established the Mint of the United States, and made both gold and silver legal tender. This meant that anyone could present bullion at the Philadelphia Mint and receive it back, struck into coins. The 1792 act authorized six silver coins, in value from five cents to a dollar, and prescribed their weights and fineness. Making a dollar equal to given quantities of both gold and silver made the currency vulnerable to variations in the price of precious metals, and U.S. coins flowed overseas for melting until adjustments were made to their size and weight in 1834 and again with the Coinage Act of 1853, when the amount of bullion in the silver coins worth less than a dollar was reduced.