So it's time to buy some new wheels. What hardness should you get? What do the durometer numbers mean? What's a durometer anyway? Don't worry, we got you. All skateboard wheels are made from urethane, ...

Rockwell hardness testing is a method of determining the relative hardness of a material. In this test, hardness is measured by determining the depth of residual penetration by a steel ball or a ...

The hardness of a material is defined as its resistance to another material penetrating its surface and is related to its wear resistance and strength. Higher hardness is related generally related to ...

A groundbreaking scale that redefines gemstone durability by combining hardness, fracture toughness, and inclusions into a comprehensive framework for the gem and jewelry trade. BURLINGTON, Vt., Oct.