potassium feldspar
Dolomite has a Mohs hardness of 3.5 to 4, making it relatively soft compared to many other minerals. It can be scratched easily with a knife or nail, but can scratch materials like calcite.
Quartz scratches dolomite but is scratched by olivine. Dolomite has a Mohs hardness of 3.5-4, while quartz has a hardness of 7. Olivine, on the other hand, has a higher hardness of 6.5-7.
Quartz scratches dolomite, while olivine scratches pyroxene.
Yes, a knife can scratch dolomite because dolomite is relatively soft, with a Mohs hardness of around 3.5 to 4. This means it is softer than the steel blade of a knife, which typically has a hardness of around 5.5 to 6.5 on the Mohs scale.
apatite with a steel knife feldspar with window glass
Mineral that can be scratched with a knife blade or a window glass is gypsum.
Minerals that have a hardness less than that of a knife blade (5.5 on the Mohs scale) can be scratched with a knife. These minerals include gypsum, calcite, and talc.
soapstone
Minerals that can be scratched by a knife typically have a Mohs hardness of less than 5.5. Common examples include talc, gypsum, and calcite, which are softer minerals. A knife, generally made of hardened steel, can scratch these softer minerals, while harder minerals like quartz or diamond cannot be scratched by a knife.
The hardness of dolomite ranges from 3.5 to 4 on the Mohs scale. It is softer than most other minerals and can easily be scratched by harder minerals such as quartz or topaz.
Minerals that can be scratched with a knife blade but not with a copper coin typically have a hardness between 3.5 and 5 on the Mohs scale. For instance, minerals like calcite (hardness 3) can be scratched by a copper coin but not by a knife blade, while minerals like fluorite (hardness 4) can be scratched by a knife but not by a copper coin. Therefore, minerals like fluorite would fit your criteria.