Answer:Examples of valuable nonmetallic minerals extracted by mining are sand, gravel, phosphate
Step-by-step explanation:
Nonmetallic minerals refers to those chemical elements that cannot be used to make any other products after they have been melted. Examples of these minerals are clay, limestone,marble , sand and gravel. They are called non metallic because they can not conduct electricity , can not conduct thermal power, they lack luster,rigor and malleability.
The non metallic metals are mostly used to make cements , lime and glass.
They can also be used in sanitary ,tableware and decorative products.
Several steps are followed in making certain products from these minerals such as grinding,cutting,mixing,shaping and heating.