Calcium oxalate in the three different, and known, crystallographic
forms (whewellite CaC2O4H2O, COM; weddellite
CaC2O4(2 + x)H2O, COD and caoxite CaC2O43H2O, COT) shows
properties which turn out to be of great interest in various fields
of material science, namely biomedicine, mineralogy and cultural
heritage. The characterization of these materials is essential also
for the benefit of a quick analytical recognition, but so far it is
not so easy to be carried out with physico-chemical or chemical
techniques.