Free-form. A medallic shape without any geometric or symmetric form. Free-form shapes are amorphous without any straight or round edges. Not bound by constraints or usual medallic conventions, free-form shapes are naturalistic and highly artistic, symbolic of freedom of design. They are determined only by the shape the design dictates and are not prescribed by prior notion or ideals. When only a portion of the edge has this treatment it is called partial free-form (the other part is conventional). An example is a portrait medal by French medalist René Gregoire, which is silhouetted around a hat, the remaining shape is free-form.

Free-form shape is close to the Chinese concept of "oil spot" – the outline of a drop of oil takes as it floats on the surface of quiet water and takes the shape dictated by wind and water currents, easily expanding in any direction.

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A27 {1969} Mayer p 154.