Third in the list of Building Materials is Sand. It may also refer to some textural class of soil or soil type; i.e., a soil containing over 85 percent sand-sized particles in bulk.
The composition of sand varies, depending on the local rock sources and conditions, however, the most frequent constituent of sand is silica (silicon dioxide, or SiO2), normally in the kind of quartz.
The next most frequent kind of sand is calcium carbonate, by way of instance, aragonite, which has largely been generated, within the last half billion decades, by various types of life forms, like coral and shellfish.
Sand is popularly used in concrete.