The strongest area of interest for me in numismatics is in ancient coins.
That is also the area where I have spent almost all of my edcational effort in learning how to identify fake coins, but most of the rules below should apply to
all coin collectors.
This is my strategy developed to that end:
1. I maintain an extensive collection of fake ancient coins, ranging from obviously fake to highly deceiving.
2. I have easy access to XRF testing equipment. Actually so do most other coin collectors; just ask your local bullion dealer.
3. Extensive experience with style an fabric coupled with weight are very useful factors in the identification of fake ancient coins. I will never be out of a state of development in this regard.
4. I have a small library on the detection of fake coins and on the various methods of their manufacture.
5. I have a library of about 70 books and researsh references on ancient coins.
6. The various data bases to be found on the 'net on fake coins are a very useful tool in proving the authenticity of a coin that requires investigation.
7. I have maintained a strong numismatic friendship with probably two of the most experienced dealers in ancient coins in Australia for over 30 years, both of whom are international auction lot describers.
8. For all of my more significantly valuable ancient coins, I have only bought from dealers or auctions of the highest reputation and experience. I have kept the invoices for all of these coins in a separate folder for over 30 years. The maintenance of an invoice record helps to establish or extend provenance, should the coins need to be sold.
9. I always like to see any coin in hand before making a decision to buy. That, for the most part, precludes me buying coins on
ebay, although if the seller is of the provable reputation as decribed above, I cannot see why buying on
ebay should stop me.