Rhenish tuffs from the volcanic Eifel region, Germany, have widely been used as building stone in the Netherlands. Different kinds of tuff (Romer, Weiberner, Ettringer, Riedener) show different kinds of decay, and also within each group, remarkable differences in weathering behaviour occur. In the present study, a short introduction is given to the historic use of tuff in the Netherlands, and a survey of weathering patterns is presented. Fresh quarry samples and material removed from several Dutch monuments have been studied by polarization-and-fluorescence microscopy (PFM) and X-ray diffraction analysis fiRD). So far, no relationship between mineral assemblages and durability could be established.