Engine turning is a method of decorating metal surfaces with precise, repeating patterns of fine lines cut by a machine called a rose engine or straight-line engine. The object is held against a cutting tool while being rotated or moved in a controlled way, producing intricate geometric designs such as basket weave, wavy lines, sunbursts and barleycorn.
The technique, also called guilloche, developed in the eighteenth century and reached its height in the nineteenth century, when English and French craftsmen used it extensively on silver and gold snuff boxes, cigarette cases, vinaigrettes, watch cases and watch dials. Engine-turned surfaces catch the light attractively and disguise minor scratches, which made them ideal for objects carried in the pocket. Under translucent enamel, engine turning creates a shimmering effect seen on Faberge pieces, French clocks and Art Deco vanity sets. Engine turning was also applied to brass lamp bases and other decorative fittings. Collectors look for crisp, unworn patterns with sharp lines; heavy wear, polishing or dents soften the pattern and reduce value. On silver, clear hallmarks and good gauge add to the appeal of engine-turned boxes and cases.
