Diamond Drilling Tools – Core, Solid & Specialty Bits

Our diamond drilling tools are designed for precision drilling in gemstones, glass, tiles, ceramic, and stone. Explore core bits, solid drill bits, specialized bits, and multi-size drill bit sets for professional lapidary and industrial use.

Related Tools

• Water Swivel Adaptors — rotary water feed for internal cooling during core drilling
• Sintered Diamond Burrs — ball, flame, cone & cylinder burrs for jewelry carving and stone setting
• Diamond Carving Burs — resin and sintered burs for stone, glass, and gem engraving
• Diamond Polishing Compounds — finish drilled holes and edges after drilling
• Diamond Smoothing Pads — clean up and polish surfaces around drilled areas
• Lapidary Machines — drill presses and lapidary equipment for drilling setups
• Machine Accessories & Parts — arbor adapters and mounting hardware

Frequently Asked Questions

• Q: Which drill bits are best for drilling holes in gemstones for pendants and beads?
  A: Solid diamond drill bits (0.5–12mm) are ideal for small precision holes in gemstones, agates, and crystals for pendant and bead making. Always use water cooling and low speed (500–1000 RPM) to prevent cracking.
• Q: What is the difference between electroplated and sintered diamond core drills?
  A: Electroplated core drills have a single layer of diamond on the surface — they cut fast but wear out sooner. Sintered core drills have a multi-layer diamond matrix that self-sharpens as it wears, lasting 5–10× longer and performing better on hard granite, quartz, and tough stone.
• Q: Do I need a water swivel adaptor for core drilling?
  A: Yes — for core drills used in a drill press or rotary tool, a water swivel adaptor feeds water through the center of the bit for internal cooling. This prevents overheating, extends bit life, and produces cleaner holes in stone, glass, and ceramic.
• Q: Can diamond drill bits drill through glass without cracking it?
  A: Yes — use a diamond core drill or solid diamond bit with continuous water cooling, low speed (300–800 RPM), and light pressure. Start at an angle to create a starting groove, then drill straight through. Avoid dry drilling entirely.
• Q: What size core drill do I need for a standard stone tile hole?
  A: For standard electrical outlet or pipe holes in stone tile, use a 68mm or 82mm sintered diamond core drill. For smaller decorative holes, 20–50mm core drills are common. Always match the drill diameter to your intended use.
• Q: What are sintered diamond burrs used for in jewelry making?
  A: Sintered diamond burrs (ball, flame, cylinder, cone shapes) are used for carving stone settings, engraving gemstone surfaces, shaping prong seats, and detail work in hard stone jewelry. They outlast electroplated burrs significantly in professional use.