PROVIDENCE, R.I., June 7, 2010 — Miniature precision sapphire and ruby balls for use in medical and chemical pumps as check and metering valves, as ball and roller bearings, and as endoscope lenses and stylus tips are available from Meller Optics Inc. They are second only to diamond in hardness to provide good wear resistance, have a 2000 °C melting point, and are impervious to most chemicals, solvents, and detergents. Suitable for applications in medical devices and instruments, these miniature precision balls are offered in 42- in. and metric sizes from 0.1 mm to 0.5 in. in diameter. Featuring Moh 9 hardness (Knoop 1800 perpendicular to the C-axis), they have surface finishes of 20-10 scratch-dig or better and can be precision ground and polished in half or to a specific diameter and center thickness to make an inexpensive planoconvex lens, and they can be drilled for use as bearing rollers. They can be used as spacers in metrology applications, in flow meters, bar-code readers and fiber optics. They are priced according to material, size and quantity.