A few minerals that do not scratch glass come to mind . . . talc, asbestos, mica, for instance.
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Selenite will not scratch glass because it has a hardness of 2 on the Mohs scale, while glass has a hardness of around 5.5. This means that selenite is softer than glass and cannot scratch it.
Diamond is the hardest mineral that can scratch a steel knife or window glass.
A mineral that will scratch with a window glass but not with a knife blade is a mineral with a hardness between 5.5 and 6.5 on the Mohs scale, such as orthoclase or peridot.
Quartz will scratch glass, as its hardness is usually around 7. Pyrite, on the other hand, has a hardness of 6 to 6.5, meaning it would not be able to scratch glass.
Diamond is the only mineral that can scratch glass but not leave a streak on a streak plate. Glass has a hardness of around 5.5 on the Mohs scale, while a streak plate typically has a hardness of around 6.5. Diamond, with a hardness of 10, is able to scratch glass but not the streak plate.
The mineral has a hardness of around 3.5 on the Mohs scale if it can scratch a penny but not glass. Minerals with a hardness of 3.5 include minerals like calcite and copper.