My mom runs both an ICP and an ICP-MS (Mass Spectrometer) with both fresh and sw samples. So she can test for pretty much any element. It isn't likely i will actually use the stuff i guess, but i was just curious what grade is commonly used. The ICP-MS can actually detect down to the ppt (parts per trillion...yes with a t) although realistically, not being in a clean room, that doesn't particularly mean much, but definitely low enough for these needs...I think it would be really cool to test a bunch of salt mixes, I know there have been studies done on that already though.