qz plate

[Natale Perchiazzi]

Dear All,
Who can tell me where can I buy a zero-background quartz (or other material)
plate?
Thanks in advance for you attention
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               Natale Perchiazzi                           
  Dipartimento di Scienze della Terra 
       Universit� degli Studi di Pisa           
     Via S.Maria 53, I-56126 Pisa        
             tel +39 050 847269                         
             fax +39 050 40976                         
      e-mail [EMAIL PROTECTED]                
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