We experienced the exact same problem. We had contamination up to 15% on some samples. We are now only using the agate elements even though we cannot determine the amount of contamination. Has anyone tried using zirconia elements which are readily available in this size? I asked McCrone about them and the answer I got was that only the agate and corundum were recommended but that is all they sell. Can the mill handle the extra weight from the higher density elements?
Doug Allen Sr. Mineralogist Phelps Dodge Mining Co Process Technology Center 928-348-0838 -----Original Message----- From: Mati Raudsepp [mailto:[EMAIL PROTECTED] Sent: Thursday, October 26, 2006 7:33 AM To: [email protected] Subject: McCrone Micronizing Mill Users - New Style Corundum Elements 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 This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail. Este mensaje (incluyendo los archivos adjuntos) esta dirigido solo al receptor senalado y puede contener informacion de caracter privilegiada, privada o confidencial. Si usted no es el receptor senalado o bien ha recibido este mensaje por error, por favor notifique inmediatamente al remitente y elimine el mensaje original. Cualquier otro uso de este mensaje de correo electronico esta prohibido.
