Drill clean, precise micro holes in glass, stone and ceramic (1–3mm). These Small Diamond Core Drills (1.0–3.0mm) are perfect for sea glass, beads, gemstones, porcelain, glazed pottery, pebbles, slate, optical glass and composites. The hollow core clears slurry, runs cooler and helps achieve chip-free entry/exit on brittle materials—ideal for jewellers and glass artists. Best practice: Drill under water with the work supported on a rubber block. Run at slow to moderate speed (max 10,000 RPM) and use very light pressure, pulsing up and down to clear slurry. Sizes: 1.0, 1.5, 2.0, 2.5, 3.0mm (select below). Bond: Electroplated diamond. Coolant: Water. Usage Guide 1. Submerge the work on a rubber block in a shallow dish of water. 2. Mark the hole; start at a slight angle to create a bite, then level out. 3. Use light pressure; pulse the drill up and down to clear slurry, always keeping the crown wet. 4. Stay under 10,000 RPM. Deburr edges afterwards with a diamond ball burr if required. Core vs Solid Diamond Drills Core drills remove a tiny plug and run cooler on brittle materials—perfect for 1–3mm holes in glass and ceramic. For very hard materials (quartz, ruby, flint, fossil bone, porcelain) or when you need a solid end, use our Small Solid Diamond Drill Bits instead. ***Sold Individually*** See the Technical tab for exact dimensions and collet/chuck guidance.
