These bamboo coral beads are 6 x 3mm. Smooth and polished. Yes, these are dyed, but who cares? They are beautiful. There are very strict rules set in place regarding the importation of coral into the United States. International law protects the rarest and endangered coral in all parts of the world. Many varieties of coral are considered sustainable and in reality they grow faster than they are being harvested. These beads are hand cut as well. As with any handmade bead, please expect slight imperfections in size, shape and color.