Glass is about 6-6.5
Quartz has a hardness of 7 on the Mohs scale, making it relatively hard and durable.
Diatomite has a hardness of around 5.5 on the Mohs scale of hardness.
Flint is a type of Quartz, and Quartz is a 7 on the Mohs Hardness Scale
Obsidian and pitchstone have a similar hardness of around 5 to 5.5 on the Mohs Scale of hardness. This means they are relatively hard materials and can scratch glass, but they can still be scratched by harder materials like quartz.
A typical steel knife would be in the 5-5.5 range on the Mohs scale.
Quartz has a hardness of 7 on the Mohs scale, making it relatively hard and durable.
Diatomite has a hardness of around 5.5 on the Mohs scale of hardness.
The hardness of the mineral pyrite, or Fool's Gold, is about 6 on the Mohs hardness scale. That's a little harder than a steel knife blade, but not as hard as the mineral quartz
It is about 2.5 in the Mohs Hardness Scale.
Flint is a type of Quartz, and Quartz is a 7 on the Mohs Hardness Scale
Obsidian and pitchstone have a similar hardness of around 5 to 5.5 on the Mohs Scale of hardness. This means they are relatively hard materials and can scratch glass, but they can still be scratched by harder materials like quartz.
Kaolinite is a 2 on the Mohs Hardness Scale.
The hardness of uranium is 6 on the Mohs scale; not so hard.
This scale is correctly called the Mohs scale. Scientists use this scale to measure a rock's hardness or softness. They can discover how hard a mineral or rocks is and drill in to it and find out more about it.
Glass is about 6-6.5
Opal has a hardness of 5.5 to 6.5 on Mohs Scale
A typical steel knife would be in the 5-5.5 range on the Mohs scale.