In order to obtain a very rough estimate, you will need to take several photographs of the item and submit them to a specialist. It you want a more precise estimate, you should make appointments at several auction houses and bring in your item. It could be worth $10, it could be worth $1000s.
Good advice from Elizabeth. Before you take the pics, call Sotheby's & ask them about the photo angles they want to give uou a rough estimate. Recognize that their estimate may be: "Interesting, but we have to see it in person."
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