Your ring could very well be a period ( 1860's) ring. Signet rings go back to Roman times. In Latin signet means "sign" and they could bare a coat of arms, initials or surname on them. Although this one has not been engraved. The fact that yours is not marked inside the band is even more proof that it is old and probably is made from coin silver. It looks small so maybe a ring from a soldier's sweetheart?