We have been using the McCrone Micronizing mill for many years with the pink corundum grinding elements with good results. Generally, contamination from the grinder ranged from not detectable to a maximum of 1-3 wt.% depending on the specimen. Most of the material we grind is quartz/feldspar rich rock. Recently we got the new style elements which are white, not as well finished and look slightly porous relative to the old elements. Regrinding old specimens as a check now gives about 7-10 wt.% contamination from the elements. McCrone admits having complaints about the new elements but I have not had a chance to follow up to see if there is a solution.
Have any of you McCrone users found the same problem with the new white elements?
Mati Raudsepp, Professor (Hon.) Director: Electron-microbeam/X-ray Diffraction Laboratory Department of Earth & Ocean Sciences 6339 Stores Road The University of British Columbia Vancouver, BC V6T 1Z4 Tel: 604-822-6396 Fax: 604-822-6088
