PRESIDIUM Duo Tester Mode D'emploi page 16

Place the gemstone on the metal stone rest and hold the
metal stone rest with one hand while holding the probe with
the other hand (Fig. 2.2).
Performing an optical test with your Presidium Duo
Tester
Replace the protective cover with the cylinder and press
the "DISPLAY" button. The display will give "000" reading
(Fig. 2.3).
Fig. 2.3
Remove the cylinder and place a well-cleaned, polished
gemstone on the centre of the pad
(Fig. 2.4)
Fig. 2.4
Cover the gemstone with the recessed cylinder (Fig. 2.5).
Fig. 2.5
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