IO salt assay by Craig Bingman, using ICPMS, in 1999.
Ca++ = 361
Mg ++ = 1264
IO assay by IA, using ICPMS, in 2005
Ca++ = 340
Mg++ = 1400
Ron Shimek's assay from 2002 tested by AM TEST LABORATORIES, INC. using ICP
Ca++ = 400
Mg++ = 1400
other assays we say are untrusted
ICP method
Ca++ = 372 - 425 avg 398
Mg ++ = 1273 - 1296 avg 1284
ISE method
Ca++ = 206 - 503, avg 374
Mg ++ = 1084 - 1358, avg 1221
The only way to verify anyhting here is to test a salt you have with 2 trusted test kis, record the numbers and send a split sample to ENC Labs to see what they get.