Care and Maintenance of Collectible Knives.
This section addresses the cleaning and storage of collectible knives. Be advised that using knives are a different story and will not be addressed here.
Cleaning
Every knife should be cleaned regularly, especially valuable handmade collectible knives. All steel, "stainless" or not, is susceptible to oxidation and corrosion, these are normal properties of the carbon in steel.
Fingerprints and moisture are the main detriments to the preservation of collectible knives. Knife blades must be kept dry. Fingerprints and moisture must be removed from knives after handling. A soft all cotton cloth or chamois are best for this task.
After handling and wiping down knives apply a couple drops of quality oil (I like Break-Free and Rem Oil) to the blade and other metal surfaces with a soft cotton cloth. I am also partial to a product such as Tuff-Cloth. A good wax, such as Renaissance, is also excellent protection and is especially appropriate for the non-metal portions of your knives, i.e. handles. Not all finishes, natural or exotic materials respond well to the same cleaning agents, so do a little research and most importantly follow the makers advice for care.
For folding knives keep the locking mechanism clean and free of debris. Apply a drop of light oil at each joint and work it into the action to keep it functioning smoothly.
Knives should be checked periodically for trouble spots. Prevention is the best medicine to avoid having to clean up problems after they develop.
If you see tarnish or oxidation develop, this could be the start of rust and should be cleaned as quickly as possible. Try soaking the affected area overnight with a quality oil, such as those used to clean and preserve guns, then wipe it down the next day. If stains are present try removing the stain or tarnish with a metal cleaner or polish such as Flitz or Simichrome.
Storage
Your knife collection should be stored in a room that has low humidity and is cool.
Avoid areas with a high relative humidity and those that experience a significant shift in temperatures. If you live in an area where it is humid use silica gel or other desiccants to help keep your knives dry.
Never store knives in leather sheaths. Store them separately because leather absorbs moisture and can rust your blade. Tanning salts and acids in the leather can also rust or tarnish steel. Leather sheaths should be treated with a leather preservative or mink oil.