The Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. It was created in 1812 by the German geologist and mineralogist Friedrich Mohs and is one of several definitions of hardness in materials science. Try to name as many minerals on the scale as you can in 3 minutes!
Both in high school (Bailey Magnet School, Jackson, MS) and in college/university (University of North Texas), our teachers and professors used a mnemonic device to teach us this, and for #6, they always used an "o" word (for "orthoclase"). Examples: "Tall Gypsies Can Flirt And Other Quaint Things Can Do", "Tall Gypsies Can Flirt and Other Queens Too Can Dip". I remember this very clearly. In these quizzes on JetPunk.com, alternatives are often allowed and typing in one correct answer will bring up the other. Surely there is a way to correct this quiz? Or, once created, can a quiz not be modified? I will have to experiment with this myself. I need to come up with a good quiz to make investigating this worthwhile.