Weather vanes are believed to have been in existence since the days of the ancient Romans and Greeks, explains Denninger.com. Over the centuries, weather vanes have been created and used by artists, professionals and common people to show the direction of the wind and, in come cases, predict the weather. According to WeathervanesPlus.com, antique weather vanes have been known to sell anywhere from $50,000 to $750,000 and more. Today, it can be difficult to determine the precise age of an individual weather vane. However, experts on the subject may be able to narrow down the approximate age based on its design, the materials used and any identifying marks its maker may have left on it.
Examine the weather vane closely. Photograph the weather vane from several angles. Write down observations about any unique details. For example, if your weather vane has gold leaf accents, it may help you narrow down when it was manufactured.
Identify and take note of what materials the weather vane is made of. They have been made out of a wide variety of materials. In his article on WeatherVaneSale.com, author Michael O’Brien notes that antique weather vanes made out of materials such as copper and iron will show normal wear and discoloration. “Over time, copper will develop a green patina as certain elements in the copper begin to oxidize. Antique iron will show signs of oxidation,” O’Brien writes. He also notes that if you are in possession of a weather vane that appears to have signs of aging and oxidation, you should not attempt to clean it. O’Brien warns that attempting to clean a weather vane “can remove or mar valuable patinas, oxides, paints and other elements that can help to establish the age of the weather vane.” He recommends having the weather vane cleaned and restored by a professional.
Search the weather vane for any kind of identifying marks from the maker. If you find any intentional markings or brands, make note of it and photograph it. Over the last several centuries, it has become more common for weather vanes to be produced and marked by its maker. L.W. Cushing, J. Howard and Company, J.W. Fiske, J.R. Mott, E.G. Washburne, Cushing and White, Harris and Company and the Rochester Iron Works were noted weather vane makers. If the mark of a well-known maker is located on a weather vane, or if it is otherwise dated, it is possible to figure out when it was created and how old it is.
Compile everything that you know about your weather vane into a single point of knowledge. Include pictures of its distinct features, notes regarding its composition and makers’ mark and use your information as a starting point for your online research. Pick a feature as a search term. For example, if you have a rooster weather vane featuring a Rochester Iron Works maker's mark, type it into a search engine and review the results. Compare your weather vane to other similar items from the same maker and this may give you an idea as to when your weather vane was manufactured.
Contact an expert if you are unable to determine the origin of your weather vane by examining it or tracking its identifying features. O’Brien claims that weather vanes are one of the most difficult antiques to value because of the long and largely undocumented history behind the pieces. For further assistance determining the age of your weather vane, contact an antiques and collectibles or folk art professional in your area.