French, Flour Bag Seal, Moulin d'Apigné Seal, Image & Found by Simon Gezzy Guerin.
Found on Guernsey, 15mm.
M.M. / J // MOULIN curved down D'APIGNÉ curved up around
Identified by Paul Cannon, "I am now fairly sure that this seal reads MOULIN D'APIGNÉ. Apigné is an area close to the western side of Rennes in Brittany. The ancient mill, which had been rebuilt in the 19th century, went into bankruptcy in 1904 and the site subsequently became a brick factory. Part of the old mill buildings are now a restaurant. See Ancien moulin, puis briqueterie d'Apigné (Rennes) - Inventaire Général du Patrimoine Culturel (region-bretagne.fr)
I would suggest the seal predates 1904. Both of the two known examples of this seal have been found in Guernsey, which is close to the Brittany coast and hints at the possible sources for flour in Guernsey during the 19th century."