A few thoughts after forty years of collecting knives;
There are two categories of knife collectors - those who buy knives with the intention of using them and those who buy them for the pleasure of admiring and playing with them with the ultimate hope that they will appreciate in value over time.
My criteria for buying user knives over the years has been mainly based on the quality of the steel and feel in the hand plus blade design will determine its capacity to perform specific tasks.
Collecting investment knives is a much like collecting anything and there are some basic rules which I have found helpful to maximise the potential for a knife's future value. Although with the odd exception, knives generally do not make great investments.
The main things I look for when buying an investment knife are:
1. Maker's Mark
The maker's name stamped on the blade. This is critical for custom knives and has the biggest influence on future value.
Not so important with production knives where approx 85% were not actually made by the company whose logo is stamped on the blade.
Rarity is essential for investment knives and in my experience custom knives by low volume producers are the best for future capital appreciation.
Those high volume makers irrespective of their popularity or the quality of their knives rarely make good investments.
Look for and be prepared to take a punt on the up and coming makers rather than the "name" ones where you will pay top dollars with minimal prospects a return on your investment.
Those promising makers who subsequently make it as top custom makers offer the best chance of maximising your investment dollars.
Historical knives are generally great investments because they are rare; Plus they are linked to specific moments in time. But supporting documentation and authentication are important requirements.
Condition is extremely important as is fit and finish and with folders blade centering and lockup. Unused, pristine knives, preferably with their original sheath bring the top dollars.
A mere scratch on a high end custom knife can reduce its value by half and any signs of rust or oxidization can kill a knife's value.
6. Record Keeping
Record as much information as you can about every knife when you purchase it and maintain a database for your collection.
If buying direct from a custom maker ask him to sign the sheath or a business card - this can add to the future saleability of the knife.
7. Avoid Market Hype
Knife Shows can be a bad place to purchase investment knives.
Many buyers are influenced by the hype of the event and makers are usually reluctant to discount their full retail asking price.
The resale market, auctions, estate sales, forums etc are usually far better value than the Knife Shows and getting to know specific makers and buying direct can result in significant savings.
Knife collections should preferably be stored in airtight containers and knives should never be stored in sheaths.
Carbon steel knives are prone to rusting and oxidation and must be maintained regularly with the occasional wipe with machine oil.
9. Keep Up To Date
Collectors are advised to monitor the progress of the makers of the custom knives in their collection and when it is obvious that a particular maker has not made the grade for whatever reason, they should consider quitting that knife and replacing it with another with better potential.
In summary collecting investment knives can be a very enjoyable but challenging pursuit and to be successful it is necessary to take an objective not subjective approach.
In most occasions those knives that meet this criteria are the nicest ones anyway - good luck!