Shenglong Diamond Drill Bit Jewelry Beach Sea Glass Shells Gemstones Lapidary 60pcs. 1mm Set of 60 pcs. 1mm Diamond Drill Bits - 1/8 shank Fits drills, flex shafts and dremels.Used by Jewelry Designers for drilling clean holes Drills Beach Sea Glass, Sea Shells, Rocks, Marbles, etc. For Making Earrings, Pendents and Bracelets.