I am often asked what split rings I recommend for use in jewelry, and many people are surprised to find that split rings actually are not good for jewelry!
While split rings are wonderful for dog tags, key chains, and zipper pulls, they are not well suited to jewelry for a number of key reasons:
Exposed Ends - Split rings have two ends, just like jump rings do, but a split rings ends are exposed and can abrade your skin when used in jewelry while a jump rings ends are closed flush to each other.
Snagging - Due to those exposed ends, split rings can also snag sweaters and hair, especially if they have spread. If a jump ring is closed properly, it should never snag or scratch.
Spreading - Yes, small split rings are notorious for spreading while putting a piece together or under heavy weight and use. The resulting gap can allow a charm or connection to work its way out of the split rings grasp.
And last but not least, there is the illusion of extra security that jewelry-sized split rings give. The strength and integrity is lost in the scaling down of the gauge and size and they are no longer the safest connection. The size split ring that is commonly selected for jewelry use is too weak as the gauge of the wire used is too thin, usually 20 gauge(0.81mm thick) or 22 gauge(0.64mm thick). Split rings for making key chains, zipper pulls or to hang a pet tag are at least 16 gauge(1.2mm thick) or thicker.