A typical species from Quercus/carpinus forests of central Europe, as well as of sclerophyllous oak forests of the mediterranean area.

The cap is initially olivaceous green, but is oxidating to redbrown when exposed. The universal veil becomes bright lilac in a zone on the bulb margin. The gills are greyish green, sometimes with a violaceous tinge. The name C. prasinocyaneus is sometimes used for variants with more pronounced violaceous colours. It has a deep red alcaline reaction on the cap due to contents of phlegmacin. This reaction makes it easy to distinguish from other olivaceous green species, e.g. C. flavovirens and C. sulfurinus var fageticola.

It is related to C. rufoolivaceus , C. elegantissimius , C. cedretorum and C. xanthophyllus.