Which type of abrasive file is used to produce deeper and more visible scratches on the nail surface?

Coarse-grit abrasives are designed to create deeper and more visible scratches on the nail surface, making them particularly effective for tasks that require significant shaping or shortening of the nails. This type of abrasive has a rougher texture which allows it to remove more material from the nail quickly and efficiently.

Using coarse-grit files is advantageous when you are working on natural nails that require a lot of filing or when you need to prepare the nail for certain enhancements. The deep scratches left by coarse-grit files provide better adhesion for nail enhancements but should be followed up with finer grits to smooth the surface and prepare it for finishing.

Other types of grit abrasives, such as fine-grit, medium-grit, and ultra-fine abrasives, are more suited for refining the nail's surface and creating a smoother finish rather than for creating deep scratches. These abrasives are typically used after the coarse-grit files to ensure a polished and refined appearance on the nails.