Just cutting with a core drill probably is the worst choice. When drilling low quality rock (fractured) we usually go with a double split core barrel type not a single one. You can go with your first option or use a dremel like tool (with diamond cutter) to cut your specimen, after all it is a very small piece that you want.
Another choice is 'cementing' your specimen before cutting with a mixture of cement gypsum and water. Let it dry for a couple of days and cut it. You need to make something with low viscocity in order to fill gaps.

Best regards

Dr. Vasileios Antoniou


On 22/02/17 11:11, Lucy McKay wrote:
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Dear all,

 

I am looking to prepare rock samples for analysis on a machine more commonly used for metals and ceramics that needs v small samples – cylinders 12.5mm in a diameter and 2-3mm in thickness. Some of my samples are very friable. I can either cut out a cylinder of rock with a water jet then slice to the correct thickness or use a multi-cut core drill with an inner diameter of 12mm. The latter option is cheaper per sample, but I am concerned the samples may fall to pieces.

 

Does anyone have any advice on which technique would be best - or alternatives?

 

Any advice welcome.

 

Thank you,

 

Lucy McKay

PhD  Student

Department of Civil and Environmental Engineering

University of Strathclyde

Level 5 - James Weir Building

75 Montrose Street Glasgow G1 1XJ

E-Mail: [log in to unmask]