The literature on the mineralogy and petrology of the scapolite family is reviewed. The general formula was examined in the light of 126 analyses from the literature, together with 9 new analyses. Of these 135 analyses, refractive indices were available for 64. Sixty-four of the analyses were rejected as unsatisfactory, 46 were classed as dubious, and 35 were accepted as satisfactory. In the absence of complete structural information the following formula was established as provisionally suitable: