As part of our research, we have organised a global critical state testing “round robin”. The idea is to test an identical batch of tailings in a number of testing centres, to assess the reproducibility of tailings testing to obtain the critical state line is.
To provide material for this program, we have thoroughly mixed a large sample of tailings, and are about to commence shipment of sub-samples to all the participants. So far we have 15 consulting and university labs participating in the project.
Some pictures below outline the preparation, mixing, and sub-sampling process.