Those are "assay marks," most likely European, and they can tell you a lot, but it would help to have one crucial piece of information first - what country the piece was made in.
Most likely the marks indicate the following:
~ that the gold purity equals or is greater than a specific standard (i.e., 14k, 18k)
~ the town or province in which the piece was assayed - i.e., in which the gold purity was verified, and
~ the year in which it was assayed
The main problem is that different countries, and even different municipalites, used different systems. That's why it would help to have at least a country of origin as a starting point. The second problem is that these marks can wear over time, particularly in a ring, so it can be hard to match them even once you've identified the country.