Read the stamp
Sheffield Plate hallmarks
Among Sheffield Plate hallmarks, a Sheffield crown in a British silver hallmark identifies an assay office in a different marking system.
Fused sheet and exposed edges
Look at a rim, seam or worn raised surface for the layered construction. Edges can be finished to cover the copper. A maker’s device, when present, identifies the manufacturer; SHEFFIELD wording alone can simply state a location.
What to check next
EP and EPNS indicate electroplating rather than the fused-sheet process. A Sheffield crown in a British silver hallmark identifies an assay office in a different marking system. Keep construction, maker and assay devices separate.