Essai de laminage du système Martin

The Martin rolling system trials of 1888 were part of France's broader late-nineteenth-century effort to find a mechanically consistent method for producing bimetallic and clad planchets at scale — a problem that had plagued French coinage since the introduction of nickel compositions in the 1860s. These essais were never intended for circulation; they exist purely as industrial test pieces, struck to evaluate whether the lamination process could produce uniform cladding thickness across the full planchet surface.

Surviving examples vary noticeably in the adhesion quality of the nickel layer at the edges — which is itself the point: each piece is a data point, not a product.