how do you seperate iridium from sand?

Answer 1

Iridium is a metal, and has a density much higher than sand (which is usually composed mainly of the mineral quartz, though there are exceptions such as the sand at White Sands Nat'l Monument (gypsum) and the black sands in Hawaii (basalt rock fragments and the mineral olivene). You can purchase liquids that have densities higher than quartz but less than iridium and separate the two by floating away the quartz (or gypsum, or whatever rock or mineral makes up the sand). Of course, if there are other metals in the sand they will sink as well, so the process may take several liquids and several cycles to be completed.