Almax easyLab supply ruby ground grains in ampoule containing around 200 mg of small grains of variable size between 5 and 50 microns in size.
The optical grade of the starting Ruby and the annealing process is important to provide a good intensity of the Ruby peaks (R2 and R1 lines) as well as a well-defined two peaks. It has been demonstrated that such annealing process is important to avoid internal strain in the Ruby which in turn provides a reliable pressure calibrant.
All Ruby from Almax easyLab has been annealed during more than 30 days to provide the best quality. The FWHM of the R1 line has been measured as around 0.8 nm at room temperature and ambient pressure.