Hardness Pencils, set of 5 Magnification_Over 10X a 'real' strip will set

a 'real' strip will set off the buzzer

5x 200mm 3

this exactly what you see

the slightest layer of grease on the stone (e

you must understand the limitations of any tester you buy

Hardness Pencils, set of 5 Magnification_Over 10X a 'real' strip will setSummary Set of five hardness pencils. Each 'pencil' has a tip of a different hardness from No. 5 to No. 9 on the Moe scale of hardness (see 'Further Information'). Is it easy to use? Yes. See which will scratch your sample and which will not. Limitations Hardness varies from sample to sample, and it can also be different in different directions. These are for testing minerals, e. g. out in the field. They are not suitable for use on cut gemstone