10X18 with 20X12 Loupe (both triplets) More sophisticated diamond gauges A refractometer measures refraction (bending)

A refractometer measures refraction (bending) of light as it passes through the gemstone (like poking a stick into clear water)

so this weighs down to the nearest 5 points)

UK power supply for mains operation

as will some spinel

this is something that is very easy for you to do yourself with the 50g and 20g weights supplied

10X18 with 20X12 Loupe (both triplets) More sophisticated diamond gauges A refractometer measures refraction (bending)Summary A 10X magnification lens folds out from on end (18mm diameter); 20X from the other end (12mm diameter). Too see reviews of loupes, click here and then scroll down to see the difference between this and an identical looking loupe at a fifth the price. Detail A 10X magnification lens folds out from on end (18mm diameter); 20X from the other end (12mm diameter). Best quality. I always say that a good quality 10X loupe is better than a 20X loupe