3/32" dia. shanks are the jeweler's preferred standard for burs and small rotary tools. They fit the adjustable chucks found on most flexshaft handpieces as well as 3/32" handpiece collets.
Diamond Burs/Points are made from steel that has diamond particles permanently bonded to the outside. They are ideal for carving glass, stone, ceramic, and metal. They must be used with water or another lubricant.
Round Burs are useful for de-burring or enlarging holes, carving recesses for sweat soldering, and refining stone settings. Because of their shape they can be used at any angle.