Binocular Headband Magnifier, professional Magnifier Style_Head-worn Can be used as a

Can be used as a handheld magnifier

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

Used in combination these give 30 possible magnifications from 1

fine jewellery

3 of 395 button battery

Binocular Headband Magnifier, professional Magnifier Style_Head-worn Can be used as aSummary This is the type used by surgeons, instead of 'simple' lenses, they have a pair or very high quality tiny telescopes. This enables a unique combination of high magnification with a long working distance (choose the one that is best for you). Detail The optical quality of these is so good that you do not need high magnification, see our guide. As regards the working distance, sit at your workplace, sit comfortably upright, see how far it is