Suppose the piece is unsigned and you have no idea who might have created it? An art librarian at your public library or local museum can give you some educated guesses.
If you want to learn more by yourself, these are some standard books on art history that are worth plowing through:
Craske, Matthew. Art in Europe 1700-1830: A History of the Visual Arts in an Era of Unprecedented Urban Economic Growth (Oxford University Press).
Holt, Elizabeth B.G. A Documentary History of Art (3 vols.) (Yale University Press).
Janson, H. W., and Rosenblum, Robert. Art of the Nineteenth Century: Painting and Sculpture (Thames and Hudson).
Brettell, Richard. Modern Art 1851-1929: Capitalism and Representation (Oxford History of Art) (Oxford University Press).
You'll learn something different and more visceral, however, by going to museums and finding out first-hand what your treasure resembles and how others similar to it look up-close.
Expert opinions.
You'll also learn a great deal by working with an expert (for instance, an appraiser), and finding out which criteria they use to evaluate a piece of art. The standard rate in my town, Washington, D.C., is $250 (US). If you intend to insure your artwork, you must get an appraisal from a certified appraiser. Get the evaluation in writing. Be aware that no appraiser in the United States will guarantee his or her appraisals.
How to find a professional appraiser in the United States.
The American Association of Appraisers and The American Society of Appraisers are both organizations with websites you can search for a certified fine arts appraiser near you.
Maloney's Antiques and Collectibles Resource Directory is available at most public libraries. It lists auctioneers, appraisers, conservators, and others who can help you figure out more about your piece.
How to find a valuer in the U.K.
Go to the website of the Royal Institute of Surveyors. In the banner is the heading "Property". Click under that word and a list will pop up. Then click on "Arts and Antiques".
Try searching the websites of the London-based Association of Art and Antique Dealers or the International Association of Appraisers.
Free assessments, but not full-scale appraisals.
- Your local art auctioneer might have a free appraisal day. My neighborhood auctioneer, Sloan and Kenyon, does this on Tuesdays from 11 AM to 2 PM (Eastern).
Doyle's, an established auctioneer in New York City, has traveling appraisal days around the U.S., by appointment. Doyle's sells furniture, lamps, vases, pianos, etc., in addition to fine art. They also have free seminars in New York on how to buy at an auction.
But be wary of putting all your trust in an appraisal by someone who has an interest in buying or selling the work.
Though museums in the United States no longer do so, some museums in the United Kingdom still have "evaluation days" when you can make an appointment to bring in your artwork for the free assessment of a curator. One such museum is the Victoria and Albert in London.
If your treasure is picked for inclusion in the column "Queries" in Art and Antiques Magazine, an expert will give you (and the general public) their take on it for free. You must send them two color photos in addition to any data you have on it, and mail your request to:
"Queries"
Art & Antiques
2100 Powers Ferry Road
Atlanta GA 30339
Next: Find out if it has a tainted past.
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From your Guide: Nadine Granoff, professional art researcher, locates artistic needles in prestigious Haystacks otherwise known as the Library of Congress, Archives of American Art, and the National Gallery of Art Library in Washington, D.C. She's been happily doing so for the past ten years. She may be reached at her email address.

