Antique keys serve many purposes. Some people use them to make old doorknobs and locks functional again. Others collect old keys for their aesthetic beauty. For either reason, it is important to know the difference between the types of keys that are available from antique dealers. This will help you find the right key at the lowest price.
A barrel key is a short, round key that looks similar to a skeleton key. Both types of keys have a rounded shaft with a single bit on the end. The two noticeable difference between a barrel key and a skeleton key is the length of the shaft and the weight. Barrel keys usually have a hollow shaft, while skeleton keys are solid. Barrel keys often were made for locks on trunks, chests and small desk drawers.
A flat key has a flat, metal surface with a number of bits across the shaft. These bits are specific to one type of lock and are easily duplicated. Some flat keys may be marked "do not duplicate." Older flat keys probably will not carry this warning. A flat key is similar to a corrugated key.
A corrugated key is just like many modern house keys. Both types of keys have a even, metal shaft with a number of bits along the length of the shaft. The difference between flat keys and corrugated is that the corrugated key has one or two grooves that allow additional control over what type of lock it will open. Corrugated keys are common but work only with a specific lock.
Skeleton keys are one of the easiest types of keys to find. They have minimal security features, which makes them easy to duplicate. Some skeleton keys can be used in more than one type of lock. Skeleton keys are made of a solid, round shaft; flat bit on the end; and the bow. The bow is the area that you hold to turn the key. This is where you'll find interesting designs on some skeleton keys. Other keys have a simple, open design on the bow.
If you are looking for a specific key to unlock an old trunk, cabinet or drawer, you'll need to gather some information. Look for a manufacturer's name on the lock. Also look for any numbers on the lock, and try to determine what type of key the it may take.