The participation of the following people in this round robin is appreciated: Scott Schlorholtz; Iowa State University, Lilia Centeno; Centro Nacional De Metrologia, Mexico, Arnt Kern and Rainer Schmidt; Bruker AXS, Alfredo Santos and Juan Charquero; Cemex, and Stefan Leigh of the Statistical Engineering Division at the National Institute of Standards and Technology. Data from published papers of Hendrick Moeller of Krupp Polysius, John Taylor and Laurie Aldridge of CSIRO and the Australian Nuclear Science and Technology Organization, Per Suherman, Arie van Riessen, Brian O'Connor, Deyu Li, Dick Bolton, and Hans Fairhurst of Curtin University of Technology were also used in the analysis.