TABLE OF CONTENTS | Material | Uses | Main ore minerals | Formula | Sp. gr. | Occurrence |
|---|---|---|---|---|---|
| ANHYDRITE | Increasing importance as a fertiliser, and in manufacture of plasters, cements, sulphates, and sulphuric acid | ANHYDRITE | CaSO 4 | 2.95 | Occurs with gypsum and halite as a saline residue. Occurs also in "cap rock" above salt domes, and as minor gangue mineral in hydrothermal metallic ore veins |
| APATITE | See PHOSPHATES | ||||
| ASBESTOS | Heat-resistant materials, such as fire-proof fabrics and brake-linings. Also asbestos cement products, sheets for roofing and cladding, fire-proof paints, etc. | CHRYSOTILE (Serpentised asbestos) | Mg 3Si 2O 5(OH) 4 | 2.5 2.6 | Fibrous serpentine occurring as small veins in massive serpentine |
| CROCIDOLITE | Na 2(Mg, Fe, Al) 5 Si 8O 22(OH) 2 | 3.4 | Fibrous riebeckite, or blue asbestos, occurring as veins in bedded ironstones | ||
| AMOSITE | (Mg,Fe) 7Si 8O 22 (OH) 2 | 3.2 | Fibrous anthophyllite, occurring as long fibres in certain metamorphic rocks | ||
| ACTINOLITE | Ca 2(Mg, Fe) 5Si 8 O 22(OH) 2 | 3.0 3.4 | True asbestos, occurring in schists and in some igneous rocks as alteration product of pyroxene | ||
| BADDELEYITE | Ceramics, abrasives, refractories, polishing powders, and manufacture of zirconium chemicals | BADDELEYITE | ZrO 2 | 5.4 6.0 | Mainly found in gravels with zircon, tourmaline, corundum, ilmenite, and rare-earth minerals |
| BARYTES | Main use in oil- and gas-well drilling industry in finely ground state as weighting agent in drilling muds. Also in manufacture of barium chemicals, and as filler and extender in paint and rubber industries | BARYTE | BaSO |
