Analytical Instrument Accessories - Low metallic impurities (<5 ppm total metallic ash) make Pyrolytic Graphite ideal material for manufacturing atomic absorption spectrograph planchettes, crucibles for plasma vaporization, and sputter-coating scanning electron microscope samples requiring a conductive, non-metallic coating and bio-compatible material requirement. Deposited Shapes - Pyroid® pyrolytic graphite is available as custom free standing as deposited shapes, having diameters up to 18 in. (46 cm) and wall thickness of 0.050 in. (0.127 cm). Some of the shapes we manufacture are cylindrical tubes, spherical domes, rods, crucibles, trays, and shapes to match your specifications and drawings.