Quartz is one of the hardest minerals on Earth and is the second most abundant mineral in Earth’s crust. There are many different varieties of quartz, several of which are semi-precious gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings. Quartz is used to produce a variety of structures throughout the world, including countertops made of crushed quartz.
