As Joe said, I always use epoxy resin when setting pearls onto my pieces. I use two makes they are Devcon Clear which will take about five minutes to start setting and for faster work I use Araldite Instant Clear which starts setting in 90 seconds. Both of these glues are sold in double syringes so you do not have the problem of an incorrect mix. Buy your pearls as half drilled and then you can add a wire to your setting for added security.
Here is one of my lifesize, lily of the valley flowers set with pearls;
James
Bookmarks