The Kaufmann’s Stone was developed by the fly-tying author, Randall Kaufmann. Randall owns and operates the famous Kaufmann’s Streamborn shops in Oregon and Washington states and has written several excellent tying books. I would recommend any of his works to an aspiring tyer and find myself using them as a reference more often that I’d like to admit.
The Kaufmann’s Stone has become the standard stonefly nymph pattern in the U.S. It is a relatively easy pattern to tie but incorporates a few unusual techniques. The original is tied a bit more robustly than what I have tied here. I believe this is because on many coastal rivers, the stonefly nymphs get VERY large and the regulations prohibit using lead on the leader. Randall has solved both of these issues with the lead underbody system, which creates a larger chassis for the pattern as well as adds enough weight to get the fly down in fast water.
I like Kaufmann’s Stones in the spring on the Colorado and Roaring Fork. A big, meaty Stone high-sticked along the edges of a high, run-off swollen river will bring the trout to hand more often than not. I typically use a short (7 1/2′) leader tapered to 2X or 3X with no indicator or additional lead on it. Just cast along upstream and let the fly tumble on a tight line back toward you. The strikes tend to lean toward vicious. Crank a few out and stash them in your spring box…you never know when the bite will come on.