Mineral Classification — Mohs Scale

Minerals are the Earth's alphabet. Mohs's 1812 scale ranks them by hardness. The scratch test is the control. Indirect aim: geology, preparation for Earth science, classification thinking.

• Framework: Montessori
• Unit: Sensorial
• Learning area: Visual Form
• Level: Ages 7-9

Objectives

• Identify minerals by hardness (Mohs 1-10)
• Test with scratch tests
• Classify by color, luster, cleavage
• Build a classroom mineral collection

Materials

• Mineral specimens (at least 8 types)
• Mohs scale reference
• Scratch test materials (fingernail, penny, knife, glass)
• Classification chart

Instructions

1. Introduce Mohs scale 1-10. 2. Test talc (1, scratches with fingernail). 3. Gypsum (2), calcite (3)... 4. Scratch test each specimen. 5. Note color and luster. 6. Classify. 7. Label specimens. 8. Research one mineral.

Educator tip

Real specimens are essential. Even a small rock collection is enough. Connect to local geology.

Assessment

Observe accurate scratch tests and correct classification.

More from Sensorial

• Color Wheel — Chromatic Theory
• Olfactory and Gustatory Refinement
• Baric Sense — Weight Discrimination
• Color Box 3 — Grading Shades
• Chemistry Cube — Atomic Structure
• Fraction Insets — Advanced Operations Sensorial
• Exponent Materials — Powers of 10
• Geometric Solids — Surface Area and Volume