A good rock is hard to find and a hard rock is good to find.
Show off your mineral knowledge with a shirt depicting the Moh's Hardness Scale. This scale is a helpful way to determine a mineral's identity based on the mineral's resistance to scratching, ie its hardness. 1 is the softest and 10 is the hardest.
Graphics include: (1) Talc (2) Gypsum (3) Calcite (4) Fluorite (5) Apatite (6) Microcline (7) Quartz (8) Topaz (9) Corundum (10) Diamond
For the mineral collector, crystal addict, science buff.
Color: Black
Standard adult sizes
100% HW preshrunk cotton
Machine wash cold, tumble dry low