Your refractometer works good, but it's measurement range 1.4 - 2.0 RI, so it is not suitable for diamonds, whose values are in 2.37 - 2.46 RI. So that's why You see ---, means "out of range".
@@wimboing Hallo ich möchte mir das Refractometer - Modell: DGR-501 kaufen. Wie sieht es mit Ihren Erfahrung mit dem Geräte aus? Ist es zu empfehlen? MfG pit
it does not fulfill its function, just a programmable junk with one kilobit memory and with 10 different gems, none have been calculated correctly. just junk and for seller is not advised to sell such things. will not bring good luck not for you not for the time-wasting buyers!
