As mentioned in my previous post, stretching a ring to size it up is problematic, and only to be attempted with plain bands. In my more mercenary moods, I’ve always thought that repair goldsmiths should, as a “service” to their retail store owners, supply them with their very own ring stretchers. A ring stretcher, as shown, consists of a split, expandable mandrel onto which the ring is placed, and a lever, which is yanked down to expand said mandrel, thereby stretching the ring. The problem is, if there is a weak spot in the ring, say a solder joint from a previous sizing, the stresses are concentrated on that point and the ring will snap. Or, as in this case, when stones are set into the band. This ring fared quite well in the process and didn’t actually break, but stretched, more or less evenly, at each of the holes containing gemstones. Had it broken at one point, early in the process, the repair would have been a simple solder to repair the crack. As it was, however, the ring stretched, and stretched, and stretched until it was a total write-off. All to save a couple of bucks.
Leave the goldsmithing to the goldsmiths.