The Mohs Scale of Hardness, From Talc to Diamonds

Datastream Talc 1 Gypsum 2 Fingernail 2.5 Calcite 3 Copper penny 3 Tooth 5 Steel 5 Glass 5.5 Quartz 7 Porcelain 7.5 Topaz 8 Diamond 10 Start Previous: My Paparazzo: Hiring a Stalker Is Easy Next: Crunch Time: How a Mega-Shredder Reduces a Sedan to Scrap Infoporn: Think Your Time on Earth Is Short? […]