Soil

*1:Two days pre dried at 40°C

*2: One-minute high speed for deagglomeration followed by 20 sec. slow speed to put out the bigger particles. Only the bigger particles were deagglomerated a second time (clay particles use to build round balls).

*3:Your sample implies not only stones, also clay.This sample was too hard and compact to deagglomarate.

If we had pre-crushed the clusters and dried the sample for just one day before, it might show better results.