The contributions of the members of the Department of Geochemistry, Mineralogy and Petrology, University of Warsaw, to the study of the chevkinite-group of minerals (CGM) are described. The range of research topics includes: (i) geochemical and mineralogical studies of natural occurrences of the group, and attempts to relate their chemical composition to host lithology; (ii) detailed analysis of the hydrothermal alteration of CGM in various settings, with the aim of understanding element redistribution and the potential implications for ore formation. An ongoing series of high P-T experiments is providing quantitative information on the pressures, temperatures and melt water conditions under which the alteration assemblages have formed. Various spectroscopic techniques are being used to determine the structure of the CGM and to identify cation distribution in the structures.

In French and numerous other languages, there are certain noun phrases (NP’s) built around a noun coming from the commercial sphere, but which strike, whoever looks closer at them, as odd. I am thinking of NP’s like un prix cher, un loyer bon marché, a cheap price, un affitto caro, etc. Are these really, from a semantic point of view, correctly construed? In this article I analyse this question and try to give an answer to it.