Over 1,300 pieces of British and American pewter have been analyzed using energy dispersive x-ray fluorescence spectroscopy. A statisticalanalysis of the analytical data obtained for the four most important elements, tin, lead, copper and antimony, establishes general compositional characteristics for each form in both British and American pewter. Where statistically possible (i.e., where sufficient numbers of a particular style, form, or maker were available) more detailed conclusions are drawn. Objects of anomalous composition are also discussed. J.H.C. -- AATA