Art nouveau decorative arts: what to look at when you attribute glass and furniture

Art nouveau decorative arts attract fakes because the names carry a premium and the marks are simple to copy. A signature cut into cameo glass or burned into the underside of a table is the cheapest part of the object to reproduce. That is why attribution starts with how the thing was made and ends, not begins, with the mark. If the technique is wrong, the signature is irrelevant.

With glass, the questions are about layers and about what removed them. Cameo work builds up colored layers and then cuts back through them, either by acid, by wheel or by hand, and each method leaves its own edge. Acid leaves a slightly matte, softly rounded relief. Wheel cutting leaves facets you can feel with a fingernail, and mixed work is common on better pieces.

Reading a piece of period glass

Hold the object up and look at the base first. Period glass usually shows a ground and polished pontil area with fine circular scratches from use, and the wear should sit where the piece would actually touch a shelf. Even scratching across the whole underside is a warning, because real wear is uneven. Weight matters too, since many late reproductions are noticeably heavier than the originals they copy.

Marks tell you more about the workshop than about the maker. Firms marked continuously through changes of ownership, and some of those conventions are documented well enough to date a piece within a decade. Work made by the Galle firm after Emile Galle died in 1904 carries a star beside the name, which is one of the few marks that gives a real terminus. Other houses signed inconsistently, and plenty of good period glass carries no signature at all.

Furniture is harder to fake convincingly and easier to misread. The construction of a cabinet from this period should show hand cut joinery in places a machine could not reach, shrinkage across the grain rather than along it, and secondary woods chosen for cost rather than for looks. Marquetry lifts at the edges over a century, and a panel with no lifting anywhere has usually been reglued or replaced.

• 1
  Check that wear sits where hands and feet actually touched the piece across a century
• 2
  Look inside drawers and behind panels, where refinishers and forgers rarely bother
• 3
  Compare the colour of the wood in shadowed areas against the exposed surfaces
• 4
  Feel a cameo edge with a fingernail to tell acid work from wheel cutting
• 5
  Weigh a glass vase in the hand and compare it against a documented example
• 6
  Treat an unsigned piece with correct technique as better news than a signed piece with wrong technique

Japanese sources sit under most of this vocabulary, and knowing them helps you date a design. Asymmetric composition, insects and plants used as structure rather than ornament, and flat areas of contour all arrived in Europe through prints and through the export trade. A design that borrows those ideas cleanly usually comes from the years when they were new. A design that mixes them with later geometry is generally after 1905.

What to do before the money moves

Ask for the object out of the cabinet and in daylight, and take photographs of the base, the interior and every mark. Get the description you were given written onto the invoice, including the maker and the date range. If a dealer will describe a piece confidently in conversation but vaguely on paper, you have learned the real attribution. That gap between speech and invoice is the most reliable test in the trade.

Technique is difficult to fake and cheap to check, while a signature is the reverse of both.

For comparison material, the decorative arts holdings at the Metropolitan Museum of Art and the Japanese prints published through Rijksstudio are searchable without a subscription. Look at twenty documented pieces before you look at the one you want to buy. The eye calibrates fast when the reference examples are correct.