Any mineral with a Mohs hardness of 7 or greater could scratch quartz. Examples would be quartz (7), topaz (Mohs 8), corundum (9), and diamond (10).
The mineral that can be scratched by glass but not a penny is calcite. Calcite has a hardness of 3 on the Mohs scale, which is lower than the hardness of glass (5.5) but higher than that of a penny (2.5).
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.
Any mineral with roughly a hardness of 6 or more on the Mohs scale of mineral hardness could scratch glass, which is roughly 5.5 on the Mohs scale. Some minerals that could scratch glass would be quartz, topaz, corundum, and diamond.
You can tell what Topaz can scratch by looking at the Moh's Scale of Hardness. It looks at ten well known, easily available minerals, and arranged them in order of their "scratch hardness". If a specimen to be tested can be scratched by a known mineral from the list, it is softer than that mineral. If it in turn will scratch another known mineral, it is harder than that mineral. Topaz is ranked an 8 and therefore can scratch everything lower than an 8. This includes quartz, feldspar, apatite, calcite, gypsum and talc.
Fluorite is a relatively soft mineral with a Mohs hardness of 4, so it can be scratched by harder materials like quartz, topaz, and corundum. However, fluorite can scratch materials with a lower hardness, such as gypsum and calcite.
The mineral that can be scratched by glass but not a penny is calcite. Calcite has a hardness of 3 on the Mohs scale, which is lower than the hardness of glass (5.5) but higher than that of a penny (2.5).
The unknown mineral would be topaz. Topaz lies between apatite and corundum on the Mohs scale, making it capable of scratching apatite and being scratched by corundum.
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.
It can be scratched by a diamond, corundum, topaz, and quartz.
It can be scratched by a diamond, corundum, topaz, and quartz.
topaz
Any mineral with roughly a hardness of 6 or more on the Mohs scale of mineral hardness could scratch glass, which is roughly 5.5 on the Mohs scale. Some minerals that could scratch glass would be quartz, topaz, corundum, and diamond.
apatite will not scratch quartz topaz calcite or corundum
Corundum and Diamond.
You can tell what Topaz can scratch by looking at the Moh's Scale of Hardness. It looks at ten well known, easily available minerals, and arranged them in order of their "scratch hardness". If a specimen to be tested can be scratched by a known mineral from the list, it is softer than that mineral. If it in turn will scratch another known mineral, it is harder than that mineral. Topaz is ranked an 8 and therefore can scratch everything lower than an 8. This includes quartz, feldspar, apatite, calcite, gypsum and talc.
Fluorite is a relatively soft mineral with a Mohs hardness of 4, so it can be scratched by harder materials like quartz, topaz, and corundum. However, fluorite can scratch materials with a lower hardness, such as gypsum and calcite.
There are many different kinds of glass, with different hardnesses, but for the most part the hardness of quartz can be taken as a maximum value. Topaz will in fact scratch quartz, so it should scratch nearly any kind of glass.