An important point to note regarding particle sizes and HPC capacity:

The HPC machines are all rated according to nominal capacity based on bank-run material. This is material typical of alluvial deposits which contains large and small rocks, gravel, stones and sandy material. The capacity of the HPC’s spiral concentrator belt is designed to deal only with the undersize material scrubbed and screened from this bank-run in-feed which is typically around 30% of the tonnage fed to the machine. Accordingly, should you feed the HPC machine with material which is already undersize, all of this material will pass directly to the concentrator belt and the effective operating capacity of the machine will be around 30% of the nominal capacity, namely around 3 tons per hour for the HPC-10, around 12 tons per hour for the HPC-40, etc.