What is the value of a 1967 US quarter?
The same as essentially every quarter minted since 1965 - twenty-five cents. Quarters dated 1965 and later are made of copper and nickel, and don't contain any silver.
Note that US coins dated 1965-67 don't carry mint marks. The mints were operating full-bore to strike clad coins to replace the old silver ones that were rapidly being melted for their metal content. The Treasury blamed coin collectors for the shortage (to much controversy and criticism) and eliminated mint marks for 3 years to "prevent hoarding". The move had almost no effect as most hoarding was being done by speculators and not collectors.