Antiques, Guilty Until Proven Innocent!
When evaluating antiques, assume the worst. Assume everything has been replaced and/or restored. Assume it's Guilty, Until Proven Innocent!
Has an antique been restored or faked?
Restored: Keep in mind that you wouldn't want a pair of 18th century chairs unless they had been restored. Original condition is for a select few and when original condition might add to the value. (I guess I can address that at a later time...) The trick is to know what restorations belong, which are done properly or authentically and which are done well.
Faked: There are endless ways that antiques can and have been faked. There are many cabinet makers that take antique components and build something that might be more desirable, i.e., sellable. They may try to fake and manipulate the finish of the wood to appear much older than it is. As time progresses, this becomes more and more difficult as changes begin to develop their own patina. Cabinet makers have been rebuilding, restoring and "reconstructing" furniture for a very, very long time.
Here is an example I recently had to address; Someone offered me a flat top writing table to buy. These tables have been more desirable in recent years for use with computers and its peripherals with less need for storage. It was a recent convert. I have seen many large pedestal base desks converted with new legs added. (see picture below for the type of desks I am referring to) A trained eye can spot this reconstruction.
Here are a few things you can look for:
1 - You might notice underneath the drawers - slots or sockets where the pedestal cabinet base would connect to the top. A flat top writing table would not need this. But the original marks may be there.
2 - You can look at the depth of the frieze holding the drawers, usually large pedestal desks are much thicker. Does the flat top look proportional?
3 - You may notice that the new legs do not fit well with the top; the legs may not look right or the legs may be offset or off centered.
While I believe that the overwhelming majority of fine antiques should be restored, you need to know what restorations are appropriate. You need to understand why something may have been adjusted and you need to understand how it may affect a pieces value. You may not even care about the alterations. I did buy the desk.
If you are unsure, this is when you need to talk with an antique dealer that you trust. If you don't have someone local, email me or find me on twitter @dansalk for help. It is very common for people to consult with dealers or interior designers to assist them with purchases. Lastly, the most important point, if you like an antique, regardless of its authenticity or alterations, you should own it and enjoy it!