Here's a true collector's set of 1960's Washington quarters! Due to a silver shortage, 1964 was the last year for regular-issue 90% silver quarters. The Treasury Department replaced silver in the quarters with a coppernickel alloy from 1965-1967 and eliminated mint marks to prevent hoarding. In 1968, the mint marks were restored to the series, creating a truly unique story. This set of 1964‑1967 Washington quarters includes the last regular-issue 90% silver Washington quarter and three clad issues from the only years no mint marks were used – still in Uncirculated condition after 50 years.