How to estimate antique value from a photo

Identity does most of the work. A generic pressed-glass vase and a signed Daum Nancy vase can look similar in a listing and differ in price by a factor of 100. Start by pinning down category, era, region and maker in that order.

The strongest identity signals are visible: a maker mark, a signature, a factory stamp or a hallmark. Style and construction are next: dovetail joinery, hand-cut screws, mould seams, glaze crazing, wear on the base. Only when both agree do you have a confident identification.

Condition is a multiplier. A perfect example of a common item can double the average price; a damaged example of a rare item can halve it. Treat every chip, scratch, missing part, repair, replaced element and cleaning as a data point.

For furniture, original finish beats a stripped one every time. For ceramics, a hairline crack seen only under angled light matters more than most sellers think. For metals, worn hallmarks and thin plating reduce the estimate. For paper, spotting (foxing), tears and trimming all count.

Provenance turns a maybe into a certainty. Written proof — receipts, family photographs, catalog references, an old inventory — can lift a value 20 to 50% because the buyer trusts the story.

You do not need a museum-grade paper trail. A postcard showing the object in a great-aunt's dining room, an insurance schedule from 1974, a stamp in a book with a bookseller's price: all of these move the number in the right direction.

The market matters more than the object. Brown furniture from the 1990s was worth a lot; it collapsed for a decade; it is now recovering in certain styles. Mid-century Scandinavian design and studio pottery are still climbing. Silverware and cut crystal are soft.

Look at what has actually sold on eBay, LiveAuctioneers, Catawiki, 1stDibs and specialist auction results for the same maker, era and condition in the last twelve months. Two or three matching sales beat any single price guide.

Take the median of your comparable sales as the likely value. Trim 20–30% down for typical condition issues and add 10–20% up when the piece is unusually complete or signed. Then check what similar items are asking today (not sold yet) — asking prices are the ceiling.

The result is a low, likely and high range. If the range spans a factor of three or more, you have too little information. Add another photo, look up one more comparable, or ask a specialist before setting a price.