"Small" is a relative term, but, if we're talking about a dainty, thin band, engagement type ring, you're going to have to concentrate on targets in the 12-02 to 12-13 range. Unfortunately, that's also the range where you're going to find all kinds of junk targets too. Run the CTX in a mode with higher weighted frequencies, usually prospecting type modes, or, at least a jewelry mode. With it being a recent drop, you can turn down the sensitivity quite a bit to help ignore deeper targets and also keep the detector nice and stable. Use your depth meter to help zero in on only the shallow targets.