HARDNESS PENCIL 5

For testing the hardness scale of minerals. Hardness pencils are pencils with a tip made of one of the minerals on Mohs Scale.

BENEFITS AND FEATURES

These pencils are used to try and scratch a stone and observe if the pencils can scratch the gem.

Since this is a destructive method (it leaves a scratch), this test is mostly used on pieces of rough or on a inconspicuous place on the gemstone. Not many gemologists use this test as there ways to determine a gemstone’s identity.

Model: HP-5

Test range: 5 - 9 Mohs Scale

Hardness pencil: apatite-5; orthoclase-6; quartz-7; topaz-8; corundum-9.

Size: 170 x 120 x 35 mm

Weight: 170 g