Ships within 48 hours · Estimated delivery Sep 13 - Sep 18
- for reading (for the partially-sighted)
view any colour change
00 to £400
ADVANCED OPERATION: Not only do you get a reading
If it appears to turn light-and-dark it is doubly refractive
Hardness Pencils, set of 5 Options_Battery - for reading (for theSummary 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