Gemfield Jasper is fairly common in the USA and used beside for the production of cabinet-specimen or cabs also very often for flintknapping”. The common use of this material is caused by free entry to the claim - one is asked only for a small financial contribution for the preservation of the claim. The claim is located near the little town of Goldfield. First class specimen from here are showing concentricCircles, caused by the “Liesegang effect” (a chemically caused Rhythm).
Hans gamma shows a very beautiful specimen of this location on his homepage www.worldofjaspers.com.