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SGS's comminution experts use the SAG Mill Comminution (SMC) test to characterize ore samples, an important first step to grinding circuit design, optimization and production forecasting.


The SMC test is an abbreviated, less expensive version of the JK Drop-weight test.  Its key feature is that it is performed on small rocks samples size rocks or drill cores. 

Cores are cut into ¼ cylinders using a diamond saw and the test is performed as per the standard drop weight test procedure, except that only one size fraction is tested.  The test generates the A and B parameters and a drop-weight index (DWI) in kWh/t.  The test uses a single (and finer) size fraction, as well as a smaller number of specimens (100) which limits its accuracy.  Normally, the main ore zone (s) in a deposit is tested using the full procedure to calibrate the SMC test.  The SMC test is used to generate detailed mapping information on localized samples, providing they have comparable geological characteristics.

SGS's team of experienced metallurgists conduct the SMC test in combination with the JK Drop-weight test and other bench-scale tests. The data can then be used for circuit simulation.  The use of many methodologies provides you with a bankable solution that is unmatched in its rigor. Contact us to optimize the comminution design for your orebody and maximize your throughput. 

Feed Sample Requirements

The test procedure requires 100 rocks (minimum 60), or quarter core ‘cubes’, in any given size fraction of the JK Drop-Weight Test procedure. For the standard size (27-32 mm), this can be obtained by stage-crushing approximately 20 kg to passing 32 mm. Lower weight (5 kg) is often sufficient if the test is performed on smaller rocks. 

Call us today to find out more.

* Morrell S., “Predicting the Specific Energy of Autogenous and Semi-autogenous Mills from Small Diameter Drill Core Samples.” Minerals Engineering, Vol. 17/3 pp 447-451.

SAG Mill Comminution (SMC) testing in the USA

The service in which you are interested is not currently available in the USA. However, the Lakefield site in Canada is the only SGS site in the world that offers you engineering data and modeling and is able to cover your requirements. Contact us to find out more.