Students determine a mineral's hardness between five and 10 on Mohs' scale.

• Students Determine a Mineral's Hardness
• Seven Cut Minerals Mounted on Four Rods
• Rods Stamp with Each Mineral's Hardness

The neat little case tucks into a pocket, so students have an accurate gauge of harder minerals ready. Seven cut minerals, representing Mohs’ hardness measures of 5, 6, 7, 8, 8 1/2, 9, and 10, are permanently mounted on the ends of four pen-size aluminum rods.

The rods are stamped with each mineral’s hardness.