Calibration discs for Gemtest-PGI More sophisticated diamond gauges neat carrying case with stone

neat carrying case with stone holder slotted into a side pouch

check it with a diamond gauge

clip-on lid (which can also be used as an extra weighing container)

For the professional jeweller:  Sl1 and Sl2  diamonds will probably read correctly (but not guaranteed

Externally

Calibration discs for Gemtest-PGI More sophisticated diamond gauges neat carrying case with stoneDetails Spare calibration discs for GEMTEST PGI. The Gemtest PGI must be calibrated regularly to ensure it is working properly, especially if the temperature changes. This is not difficult: you place the probe on of the circles and press a button, then place it on the other circle and press a button. The only problem is: if you've lost the calibration discs.