After choosing thorns of very similar size, I file the base of them down in order to get the angle I want, then smooth the tip so they aren't dangerously sharp, then I custom make each a fine silver bezel with a sterling silver backing and post. Each set comes with large sterling silver earnuts (backs) to resist drooping. I oxidize and selectively polish the earrings to show the texture of the setting, but they can be ordered totally shiny if you prefer.
This specific pair is about 1/2 inch across, and stick out nearly 3/4 inch. If you'd like to order in a different size, just note it in the "notes to seller" section of checkout. Possible sizes range from about 1/4 inch to over 1 inch. The thorns are very lightweight.