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Heritage Auctions Appraisal Services

To Clean or Not To Clean?
By Meredith Meuwly

While Altering A Finish Can Sometimes Decrease Value, Professional Cleaning Can Also Revive The Artist's Original Work

Original image Cleaned image
Julian Onderdonk (1882-1922), Bluebonnets at Sunrise , 1917. Sold: May 2010 for $107,550.
Note that the yellow sky in first image (left) appears much clearer after cleaning.

When appraising artwork, vintage collectibles and other treasures, condition is one of the five main factors of value, with the other four being provenance, rarity, quality and fashion.

In some categories, condition has a direct impact on the value. For example, the higher the grade of coins, comics and sportscards, the higher the value. Often, condition has a minor role in valuing property. Collectors tend to be more forgiving of scratches, wear and minor repairs in antique furniture or historical manuscripts given the age and use of the pieces.

In antique paintings, the most common condition problem is that the top varnish layer is dirty and has turned from a clear glaze to a yellowed glaze. In the past, artists used linseed oil as a varnish to protect the paint layer and provide a "sheen" to the overall piece. As this varnish reacts differently to the environment than the paint layer, the varnish can crack and yellow as it collects dust, dander and smoke. Yellowed varnish can turn bright colors dark, and white areas yellow.

In antiques, paintings or otherwise, the usual rule-of-thumb is not to alter the artwork from its original condition. Altering the original finish most often decreases the value of the overall piece, but sometimes a light cleaning by a professional conservator can bring back the vivid colors and bright whites that the artist originally intended for the work. If the painting is yours and not intended for resale, then it's your choice on whether you would like to have your painting cleaned. If you intend to sell a painting that has old, yellowed varnish, ask a professional art consultant, auction house specialist, or dealer whether or not you should have your painting cleaned. They will be able to advise you if the market for your work will improve or not with conservation.

For example, the Julian Onderdonk bluebonnet landscape illustrated here arrived at Heritage Auctions with a dingy yellow sky and dirty surface. With the old varnish, the colors were dull and relatively unattractive. The experts at Heritage recommended a light cleaning before the sale to restore the original colors ... and what a difference it made! This stunningly beautiful work caught the eye of many more clients with its fresh (but not overdone) look and soared to a final selling price of $107,550.

The condition of an item matters because it can dramatically impact the value of the piece. In some collecting categories, the more pristine a piece, the more value it retains. In other areas, a few issues or repairs may not affect the overall value of the piece at all. And in some cases, a little cleaning will enhance the piece to sell for a higher price than expected.

After five years at Christie's in New York, Meredith Meuwly joined Heritage Auctions in 2007 as Senior Consignment Director in the Fine & Decorative Arts Department and currently manages the Appraisal Services department. In 2009, Meredith participated as an appraiser for the Antiques Roadshow on PBS. She is also a member of the Fine Art committee for the International Society of Appraisers and looks forward to assisting with any formal appraisal needs.