Review on Dazzling JINGLING Diamond Coated Lapidary Jewelry: Sparkle with Elegance and Style! by Bobby Frazier

These are high quality sintered diamond core bits for drilling holes in gemstones and other minerals. They are durable and can cut minerals with a hardness of 9 or less. I recommend using water as a lubricant if necessary, or another non-flammable, non-aggressive liquid where water can cause damage, such as B. liquid silicone or a fully fluorinated hydrocarbon such as perfluoropentane. Using them dry will wear them out faster, but be aware that you can get 20 a pack for about $7, making them inexpensive. I highly recommend these diamond bits!