Great Piece Of Kit Posted on February 28, 2022 by Richard Here is a histogram produced by a GSB Gamma Speca. GSB-1515-PRO Gamma Spectrometry Kit with 1.5″ Detector (gammaspectacular.com)The sample used comes from a St Austell mine collected last year.This inexpensive (around 1200$) unit gives test results in minutes from a small crushed sample.Thanks to Pat for the information