Posted 11/07/2013 5:12 pm
What you have is four normal business strike(circulating) dimes minted in Philadelphia(no mintmark). I can state this with all confidence because the 1975 no S proof dime is one of the rarest modern coins with only two known examples and a value well into the six figure range, it would be virtually impossible for you to possess four examples. In comparison, almost 600 million Philly dimes were minted sans mintmark.
