Author Topic: ZrO2 compositions  (Read 391 times)


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ZrO2 compositions
« on: December 13, 2021, 12:55:10 PM »
The  quality  criteria for zirconium oxide would be  “ monoclinic single crystals >20mesh, containing 0.00% of any element other than Zr and O”.

There is an ambiguity with regard to Zr and  Hf which always occur together in nature and the  complete separation is extremely expensive.  “Natural  Zr” has multiple meanings.  My post   refers to  as-mined   Zr with 1-3% Hf. 
The common name for “gem ZrO2”  is ….is…….. OHHHHH.  CUBIC zirconia.   

Wikipedia entries  for both  “zirconium dioxide” and  “cubic zirconia”  have the details.   

The thermodynamic fact of life is that gem ZrO2 will always have 8-30%  Y2O3 (or MgO or  CaO)  to stabilize the cubic structure, regardless of exact details of manufacture. 

FYI This material has been in use in EPMA labs since it became available in the late  1970’s.  Many brands  of commercial mounts have placed it into “minerals” selections for more than 4 decades.

The Kevex card shows that  Zr and Hf and Y X-rays all overlap in EDS. One  EPMA expert described gem ZrO2  as the “better than nothing” option for Zr.  He found that every crucible load he bought had a different composition.  And he only paid a  generous fee-per-use  for materials that came with validated chemical analyses. 

For some of us the pandemic  has brought  financial hardship.  Some are  apparently doing OK.  The deluge of offers because  that open letter mentioned  “millions  of  dollars”  is inevitable.   Having been through salesperson harassment, I would keep the lab door locked if it has a window to see who is knocking.

My last word of advice is use Wikipedia, for the fastest reliable first pass for the eyeballs BEFORE any cash is spent or instrument time is booked.