Certification of SRM 1879 Respirable Cristobalite as a Quantitative X-ray Diffraction SRM

摘要

Well characterized, highly crystalline standard materials are essential for accurate quantitative x-ray powder diffraction work. Synthetic cristobalite powder was certified as a Standard Reference Material for quantitative x-ray diffraction analysis of cristobalite content. Elemental analysis revealed only trace impurities; the largest being Al at 1000 ppm. Quantitative determination of the crystallinity of the material was performed. The certified crystalline purity of the cristobalite SRM 1879 was 98.0 weight percent crystalline cristobalite. The estimated standard deviation was 1.0 weight percent arising from a standard deviation of 0.5 weight percent due to random and inhomogeneity errors plus an estimated likely systematic error of 0.5 weight percent.