NIST-traceable certificate of analysis is available for all spheres and microspheres larger than 5 micron in diameter, including calibration grade glass microspheres (monodisperse/spacer grade), precision grade solid glass polished spheres, and cellulose acetate colored beads, which are often used as reference spheres and particle size standards due to their exceptionally narrow diameter tolerance.
Each certificate includes the following data for a single product ID:
- NIST-traceable density measurement with accuracy of +/-0.002g/cc
- NIST-traceable particle size distribution (Histogram) of a statistically significant number of particles
- % Spherical Particles, defined as particle length:width<1.1
- % Satellites, defined as a second smaller sphere attached to a larger sphere
- % Non-Round Particles, defined as agglomerates or incompletely formed spheres