Among the mineral particles that make up granite, more than 90% are feldspar and quartz, of which feldspar is the most. The feldspar is often white, gray, and flesh-red, and the quartz is mostly colorless or grayish white, which constitute the basic color of the granite. Feldspar and quartz are hard minerals, and it is difficult to move with a steel knife. As for the dark spots in the granite, mainly black mica, there are some other minerals. Although biotite is relatively soft, its ability to resist stress is not weak, and at the same time they have a small amount in granite, often less than 10%. This is the material condition in which granite is particularly strong.
Another reason why granite is strong is that its mineral particles are tightly bound to each other and are embedded in each other. The pores often account for less than 1% of the total volume of the rock. This gives the granite the ability to withstand strong pressures and is not easily penetrated by moisture.
Post time: May-08-2021