Detecting Repaired Porcelain & Art Pottery

By Douglas Eisele,
Old World Restorations, Inc.

There are different methods and types of equipment used by conservators to detect the restoration of ceramic objects, even if it may be invisible to the naked eye. Ultraviolet (UV) light is used to examine the surface of an object and to reveal adhesive residue or any substances that may have been applied over the original surface to mask damage. X-rays can also be used to show fractures that have been invisibly restored. Collectors can usually have art and antique items inspected by an experienced conservator or museum conservation lab before committing to a purchase.

Knowledge and experience are probably the most valuable tools with which collectors can equip themselves when inspecting and buying ceramic art. It is important to learn as much as you can about the object's nature and composition, and be able to confirm that it has the proper shape, size, design and glaze. Even when buying from reputable auction houses and dealers, you still should have a basic knowledge of the methods and materials that were used to create the object.

Don't be afraid to ask the seller questions like, "How and when did you acquire the object?", "Have you thoroughly examined it for damage and repairs?" or "Are you willing to document the condition in writing and provide a money-back guarantee if it differs from your representation?" (This last issue is especially important when buying over the Internet).

I recommend a visual inspection of the object in direct sunlight. Look for inconsistencies in color, decoration and glaze. When a damaged ceramic object is restored, it will usually have some type of clear non-fired coating applied over the repair to mimic the original surface glaze. In some instances, this "simulated glaze" is applied over the entire surface. Unlike original fired glazes, new acrylic coatings often contain lint or dust particles that can be seen with the naked eye under direct sunlight.

Some original ceramic glazes exhibit a network of fine cracks known as "crazing". These small surface cracks should not be restored and are nearly impossible to replicate when completing a restoration in an area of an object that is crazed. If an object has visible crazing, look for inconsistencies or the absence of crazing in suspicious areas that may indicate a restoration.

Carefully run your finger along the edges to reveal any rough spots or chips that may be hard to see. Some vases and flat objects can be lightly tapped with your finger to check for structural cracks. A cracked object will not "ring" like a bell when tapped.

I also suggest that you carry a small straight pin with you when shopping for ceramic objects. With the permission of the seller, carefully and lightly "touch" the point of the pin to the surface of the glaze where you suspect a restoration. The pin will easily slide across the glasslike surface of original fired and un-restored glaze but will not slide across, or may sink into, the simulated materials used to restore the damage. Be careful not to scratch or damage the glaze or the restoration. Some claim that a similar test can be done by touching a suspected area of an object to your teeth to reveal a difference between original and restored glazes.

Old World Restorations, Inc., is located in Cincinnati, Ohio. For more information call (513) 271-5459, visit their web site at www.oldworldrestorations.com or email deisele@oldworld-restorations.com.

Staffordshire figure grouping (ca. 1870) with old repair and missing arm.

Weller art pottery vase with restored top rim.

Pair of early porcelain candlesticks with small chips, missing leaves and old
repairs - all difficult to see on
an Internet auction site.

Detail of invisibly
restored top rim.