MAGI Application note:

Nov. 21. 2012 Mikko Åström & Alberto Scarani

Separating natural unheated spinel from synthetic and heat treated spinel

Identifying spinel with traditional gemological tools can be really easy or extremely difficult task. If natural spinel contains characteristic inclusions it may be identified by careful microscopic examination. However, if the stone is free of inclusions the job gets really tough. Most Verneuil synthetic spinels can be separated from natural stones by their slightly increased RI, but PL spectrometer gives the answer faster and more conveniently. Flux melt or Czochralski pulled synthetic spinels are whole another story, here Raman/PL spectrometer comes very handy - if not essential.


Muhlmeister, S., Koivula, J. I., Kammerling, R. C., Smith, C. P., Fritsch, E. and Shigley, J. E. (1993) Flux-grown synthetic red and blue spinels from Russia. Gems & Gemology. 29. 2. 81-98

Shen A.H., B. C. M., DeGhionno D. (2004) Lab Notes: Natural spinel identified with Photoluminescence. Gems and Gemology. 40. 2. 168-169.