If you need to test your mine’s ore as part of a comminution study, you can do no better than get a copy of SGS’s booklet Comminution Tests.

Included are brief descriptions of over thirty test that help characterize the easy (or difficulty) or breaking rock into smaller sizes so that minerals therein can be recovered. For example, here is their description of the Los Angeles Abrasion Test that I used many years ago to persuade the U.S. Nuclear Regulatory Agency that rocks in rip-rap would endure for 1,000 years:

The test determines a value reported as the percent loss. It is used in the aggregate industry as an indicator of the relative quality or competence of various sources of aggregate having similar mineral compositions. There are two procedures, one for small-sized coarse aggregate, and one for large-sized coarse aggregate. The test is a batch test run in a standard 28” x 20” ball mill with one 3 ½ “ lifter bar to give combination of abrasion and impact. The sample is screened at the end of the test at 1.7 mm to determine percent loss.

If you are in doubt as to which test to order, some guidance is available in a technical paper reproduced in the book. The paper is An overview of the small-scale tests available to characterize ore grindability by Andre McKen and Steve Williams. Here is the abstract from the paper:

Several grindability tests, at various scales, have been developed over the years for different applications, from conventional circuits to autogoneous grinding, and they all have strengths and weaknesses. The traditional approach to AG or SAG mill design is based on the testing of a large bulk sample in a pilot mill, has been gradually supplanted by increasingly smaller tests, down to a few kilos in some cases. This reduction in “sampling effort” was necessary, but it occurred at the expense of simplifications in the test procedures and reduction in test deliverables. This paper summarizes the current status of grindability testing for AG/SAG mill analysis and design.