Dillinger Laboratory Reference Materials are selected from industrial lots, covering the ranges of composition as completely as possible. They are thoroughly mixed to obtain a homogenous sample of adequate grain size.
Millings are sieved. All samples are bottled in a gas tight manner.
The reference values are obtained after preliminary multi-element analysis by a complete reconstitution of the test sample using pure and ultrapure compounds as primary references which have been tested before use (Staats, C., Fresenius Z. Anal.
Chem. (1983) 315: 1 – 5 and (1988) 330: 469 – 477). Synthetic macrosamples were prepared according to: Staats G., Fresenius Z. Anal. Chem. (1989) 334: 326-330. The intervals of uncertainty (P = 95 %) for the certified values typically range between 0.1 % and 0.2 % relative to contents of the main elements and between 0.001 % and 0.002 % absolute for additional elements. Values of oxygen are included for information
only.