The correct answer is E. All the above.
Pyroxene is a group of inosilicate minerals with the general formula XY(Si2O6), where X can be Ca, Mg, Fe, Mn, or Ni and Y can be Al, Fe, or Mg. Pyroxenes are common in mafic and ultramafic igneous rocks, and they are also found in metamorphic rocks.
Pyroxenes typically form prismatic or tabular crystals, and they can be either monoclinic or orthorhombic in crystal structure. The color of pyroxenes varies depending on the composition, but they are typically green, brown, or black.
The density of pyroxenes ranges from 2.3 to 3.6 g/cm3, and their hardness ranges from 5 to 6 on the Mohs scale. Pyroxenes are typically opaque to translucent, and they have a vitreous to resinous luster.
Pyroxenes are important minerals because they are used in a variety of applications, including:
- Construction: Pyroxenes are used in the manufacture of bricks, tiles, and other building materials.
- Ceramics: Pyroxenes are used in the manufacture of ceramics, such as porcelain and pottery.
- Refractories: Pyroxenes are used in the manufacture of refractories, which are materials that can withstand high temperatures.
- Jewelry: Pyroxenes are used in the manufacture of jewelry, such as rings, necklaces, and earrings.
Pyroxenes are a valuable group of minerals with a wide range of applications.