CHEMICAL-IDENTIFICATION OF PORTLAND CEMENTS IN NEW-ZEALAND CONCRETES .1. CHARACTERISTIC DIFFERENCES AMONG NEW-ZEALAND CEMENTS IN MINOR AND TRACE-ELEMENT CHEMISTRY

A minor and trace element survey of New Zealand cements, which included all the rare earth elements, using ICP-MS, ICP-AE, AA, and AE spectroscopy showed that chemical ''fingerprints'' for all sources can be defined. These reflect the geology of their raw materials modified through variable depletion of the volatile elements in the kilns. Cement identification thus has to rely on refractory elements. Such elements occurring in characteristic proportions are Ca, Sr, Ba and Mn. Rare earth distribution patterns including Ce and Eu anomalies promise more limited identification potential.