International audienceFrom in the first significant study on this kind of tool, G.C. Dunning underlined – besides their reuse as building material – their close link to the construction materials industry, that whether in England (Purbeck Marble, Quarr and Weldon Stone), or on the Continent (Caen) in his King’s Lynn study (Dunning 1977: 321, 324 and passim). Since then, the discovery in the 1970s of unfinished mortars in a Caen's stone quarry suggests a specialized activity along the bank of the Orne, river connecting the norman city to the sea. For the Purbeck Marble, the recent discovery of the 13th century “mortar wreck” west of the Poole Bay (Dorset) now concretely illustrates a full shiping load combining mortars, grave slabs and build...