CFA here is my .02.
Gerber made three versions of folding sportsman. They were I, II and III. The II has a 3.5 inch blade and the III has a 4.5 inch blade according to an older Gerber brochure that I have. Let me add here that I have a couple of each version and I sure don't think that my FS IIIs have 4.5 inch blades. Maybe if you measure from the handle to the tip. The III is a much bigger knife than the II though. I have never seen a II with gemstone scales. I have seen three model IIIs with gemstone inserts over about a 25 year period. It is a scarce knife. The knives that I have seen in person were either jade or a white material that I think may have been agate. Also, the ones that I have seen were in a Gerber display box, walnut with glass or plastic in the lid.
As far as price goes, I am going to say $200 to $300 for the FS III. But it could be worth more to a collector who needs one with onyx scales to complete a set. I don't know which of the scale materials is the scarcest but if it is onyx, that should really help the price. If it is an FS II, I don't know what should be a realistic price.
I attended an auction of 3800 knives a few years ago. These were all owned by one man. In the lot was one Gerber FS III with jade scales. If I remember correctly, it sold for right around $100. I thought this was quite low at the time, but the Case and Case Classics being auctioned were the major focus for the majority of the bidders. I wanted to bid on it but had the old ball and chain with me which necessitated severely limiting my bidding and there were a couple of items I wanted more. Otherwise it would have been mine.
As a fancier of the older Gerber knives, I think you got a real nice one.
