Rapid determination of 226Ra in environmental samples | Journal .
WEBFeb 4, 2012 · Replie sample aliquots of various environmental samples were added to 250 ml zirconium crucibles. Concrete and brick samples were ground to a fine powder with a mortar and pestle in this work but a ball mill apparatus with sieving or drill sampling could have been used. Soil samples were dried, ground in a ball mill, sieved, and blended.