Encyclopedia
Non-metallic mineral resources
Non-metallic minerals include:
a) mineral raw materials for chemical industries (salts, gypsum, barite, sulfur, phosphorites, apatites);
b) refractory, electrical engineering, piezoelectric, thermal and sound insulation, acid and alkali-resistant raw materials;
c) construction materials;
d) precious, ornamental, and technical stones;
e) other minerals not classified as metallic, fuel, or common minerals, or groundwater
Source: "MODEL CODE ON MINERAL RESOURCES AND THEIR USE FOR CIS MEMBER STATES"