Pyroxenite is an intrusive igneous rock that belongs to the ultramafic category, characterized by its dark color and high magnesium and iron content. It is predominantly composed of the mineral pyroxene, with lesser amounts of other minerals such as olivine, amphibole, or plagioclase. Pyroxenite exhibits a coarse-grained or phaneritic texture, with visible crystals, and its color typically ranges from dark green to black.
Mineral Makeup
The mineral composition of pyroxenite is dominated by pyroxenes, which are a group of dark-colored, ferromagnesian minerals. There are two main types of pyroxenes: clinopyroxenes (such as augite and diopside) and orthopyroxenes (such as enstatite and hypersthene). Depending on the specific pyroxene content, pyroxenite may also contain varying amounts of olivine, amphibole, and plagioclase feldspar.
Origin
Pyroxenite forms through the slow cooling and crystallization of mafic to ultramafic magmas within the Earth’s crust, usually at depths of 15 to 40 kilometers. The high pressure and temperature conditions at these depths allow for the growth of large crystals, resulting in the coarse-grained texture of pyroxenite. This rock type is often associated with mantle-derived magmas and can also form as a result of fractional crystallization or partial melting processes in the Earth’s mantle.
Occurrence
Pyroxenite is found in various tectonic settings, often in association with other mafic and ultramafic rocks, such as peridotite, gabbro, and dunite. It can be found in layered mafic intrusions, ophiolites, and mantle xenoliths. Notable occurrences of pyroxenite include the Bushveld Complex in South Africa, the Stillwater Complex in Montana, USA, and the Great Dyke in Zimbabwe.
Metaphysical
Pyroxenite is believed to possess metaphysical properties that promote self-confidence, emotional healing, and grounding. It is thought to help individuals connect with their inner strength and resilience, fostering personal growth and transformation. Pyroxenite is also said to facilitate communication and understanding between people, making it a powerful stone for fostering relationships and teamwork.
| Class | Igneous (Intrusive) |
| Mineral Makeup | Primarily pyroxenes (clinopyroxenes and orthopyroxenes), with possible olivine, amphibole, plagioclase |
| Luster | Vitreous to dull |
| Hardness (Mohs) | 5-7 |
| Streak | White or colorless |
| Color | Dark green to black |
| Cleavage | Good to perfect (in two directions at 90 degrees) |
| Specific Gravity | 3.0 to 3.5 |
