I am sorry to tell you, Linda, that there is no specific jump ring gauge for chain maille designs. Each weave is made using either the size ring suggested by the author of a pattern, or (with experience) the weight that will suit the chosen design.
For example, I have seen the lovely Full Persian done in a lacy 18-gauge and in a very tight 22-gauge. My advice here would be to first practice a chosen weave, within the design suggested by a chain maille author. When you feel comfortable with the pattern, then alter the gauge of the rings according to your desires, choosing a size that will work both in the weave itself, and the look you want to achieve.
Answer contributed by Dale "Cougar" Armstrong