Silver Certificates were authorized under the Bland-Allison Act of February 28, 1878. Under this Act, the U.S. Treasury was instructed to purchase $2 million-$4 million worth of silver each month from western mines. Silver Certificates were issues of paper money that were required to be backed by an equivalent dollar amount of silver in the U.S. Treasury. Each Silver Certificate was redeemable in silver to the bearer on demand. Large-size Silver Certificates measuring 7 3/8” x 3 1/8” were issued from 1878-1923. Beginning in 1928, the size of U.S. Silver Certificates was reduced to modern standards of 6 1/8” x 2 5/8”. These notes were redeemable in silver dollars until March of 1964.