Quite often, people unfamiliar with antique furniture are dumbfounded by the ability to date a piece of furniture within a few dozen years. I always get the question, How do you do that?
The short answer is that once you have seen a few thousand pieces of furniture, it all starts to make more sense. The longer answer is that there is a method to this madness, let's take English furniture as an example...
The first thing one looks at is form. Artistic movements all have characteristics that are either unique to the stylistic movement or were introduced by the movement then later adapted or outright copied by later movements. Queen Anne was mannerist, then you had the Baroque, Rococo and then Neoclassical. Elements bled between the movements, having fuzzy start and stop dates. For example, if you see a cabriole leg ending in a ball and claw foot, the earliest possible date for it on English Furniture would be the 1st quarter of the 18th Century and it could not possibly be from the Neoclassical, George III style. Legs and feet are generally the first things we look at, as new furniture styles generally changed these first.
With a starting point, one can then begin to look at other aspects of the piece to figure out how old it really is. For example, are all of the components of the piece of the same movement? Each of the movements has readily recognizable elements of design that work together visually. If you have a piece that has elements of several different artistic movements, one starts to question if it is a period piece. This can get confusing as there were transitional periods between movements and several revival periods in the 19th century that mimicked and adapted earlier design elements.
The second thing one looks at construction. In some cases, this is as complex as identifying the secondary or “carcass” wood, but there are generally some clues hidden in plain sight. Most furniture built before around 1810 was put together without metal fasteners (machined screws were not widely available until the 1840s). Joints were mortise and tenon and pegs were widely used. We look at the construction of drawers, seat blocks, the backs of case pieces and how the tops are fixed to the body. Factory made furniture, associated with the onset of the Victorian or Revival period around 1840, would have made use of screws and other fasteners as part of mass production.
While we are opening drawers and looking at the backs of case pieces, we will scratch unexposed parts of the wood to check for oxidation and look for cherf marks from saws and other indications that the piece was made with tools from the expected period. This coupled with the finish and what would be considered appropriate marks of wear and tear appropriate to the age and use of the object are clues as to the age and construction.
The final word of advice comes from my mentor...Always assume a piece is right until you have enough evidence to declare that its “Style”. That way, you are “criticizing a piece” as opposed to defending a piece. I find it makes it easier to analyze if I have a mental checkbox of what should be there.