SINCE 2001!! Boston CraftWorks is the most comprehensive site on the internet for kaleidoscope kits and parts for hobbyists, artists, students and everyone else! We have other crafts too!
Beautiful and colorful glass, dichroic cabochons. About 35mm diameter, and 3-4mm thick. Some are opaque with a black underside (like the ones in the picture here), and some are more translucent with the same gorgeous colors, but not as pronounced.