Most likely you would be testing to see if the mineral was harder or softer than the nail.
It is called a streak and its purpose is to find the hardness of the mineral.
Mineral hardness is tested on a glass plate or usually a finger nail.
Scratching a mineral with a nail is a test of hardness. It helps determine the relative hardness of the mineral compared to known substances on the Mohs scale of mineral hardness.
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You can tell if a mineral can scratch another mineral by performing a scratch test, where you use the hardness scale to compare the minerals. If the mineral you are testing can scratch the other mineral, then it has a higher hardness on the scale.
a streak test is a test wheree you rub a mineral across a streak plate to see the color of its streak, which is a better indentifying factor of the mineral than the external color. A scratch test is when you scratch a mineral to find out its hardness on the Mohs Scale of Hardness. This is also another useful identifying factor
The scratch test measures a mineral's hardness, which is its resistance to being scratched. This property is identified by comparing the hardness of a mineral to the hardness of known minerals on the Mohs scale.
A scratch test in geology is used to determine the hardness of a mineral. By scratching one mineral with another, geologists can assess which mineral is harder based on the scratch produced. This allows for the identification of minerals based on their relative hardness levels.
The answer is quite complicated in fact I don't know the exact answer. What I really know is that a geologist will probably know the exact answer. Geologists study rocks and rocks have lots of minerals. You can search the answer as well by looking at geologist websites. If it doesn't work then I hope someone else can edit this answer.
By undergoing scratch test.