Apache trail or "Gabriel" quartz called from Mexico

A variety of quartz named after the location in Mexico the so-called Apache trail, a road that the old Apache used and where this stone was found. Apache trail quartz is rare today and also has the name Gabriel quartz. Quartz is a form of silicon dioxide, SiO2. It forms more than 12% of the volume of the earth's crust. Quartz is therefore one of the most common minerals in the earth's crust. Sand and granite consist for a large part of quartz. Quartz is an important mineral in igneous rocks, such as granite. Quartz is formed when cooling a molten silicate mass. Also cooling a hot solution of orthosilicic acid can lead to quartz. Cooling must be slow. Then (large) crystals arise. Because the crystallization is rather slow, a glass often develops when the molten silica is rapidly cooled.