“…Chelating resins employing these complexing groups have been widely used for concentrating and separating mercury(II), silver(I), and gold(III) from each other (6,7) and as a group from the base metals (8,9). Other chelating resins have been of valuable assistance in toxicity studies of mercury (10)(11)(12)(13) and in recovering trace quantities of gold (14)(15)(16)(17)(18). Of these, Roster's and Schmuckler's benzyl isothiouronium resin (14) has received the most attention for its recovery of gold from sea water.…”