What is a Cerchar Test?

Geolabs Limited’s Rock Testing laboratory offers an extensive range of rock and aggregate testing, many of which are UKAS accredited.  One of our most requested tests is the Cerchar Abrasivity test that has been around since the 1970’s, but what exactly is a Cerchar test?

  • A Cerchar Abrasivity test

The Abrasivity in a rock is used extensively in tunnelling for excavation purposes. The test consists in measuring the wear of a metal ‘pin’ of a known hardness, when scratching against a freshly broken rock.


  • What does it Determine?

The Cerchar Abrasivity Index (CAI) obtained from measurement of pin wear will give a qualitative estimation of the abrasiveness of the rock from “Extremely Low” to “Extremely High” in ISRM.


Cerchar Abrasivity Test


  • Why choose a Cerchar?

Tool wear is an important parameter in mechanized tunnelling and is highly affected by rock abrasiveness.  The Cerchar Abrasivity test is key to the estimation of bit life and wear in various mining and tunnelling applications, and could save thousands by ensuring that the correct tool hardness is selected for a project.


  • What standards apply?

ISRM : Part 2 : 1974 – 2006


  • Why choose Geolabs for a Cerchar test?

Our team of experienced qualified geologists are committed to providing high quality testing and delivery of reported results within agreed timescales.

See our full range of rock and aggregate tests that we can provide at (link). To discuss your specific testing requirements please call or email Christian Clergeaud 01923 892190 for further information.