Marks that have been 'let in' on plate which has never been to 'Hall' for assay can be fairly easily detected by breathing on the suspect surface and it will be observed that the condensation of one's breath shows up the seam round the marks. However there is one particular form of this fraud that cannot be detected in this way and a knowledge of both the positioning and the form of hallmarks is necessary. This fraud involves the reproduction of late 18th century small wares, such as cream jugs, that stand on square plinths. The method used is to construct the plinth in such a way that one side of it is composed of the stem of a genuine 18th century tea spoon so that the marks appear integral with the piece and have not been 'let in' on a larger surface.