- Pyroxenes -

Choose One: Pyroxene Identification Tips - Pyroxene Flow Chart - All Pyroxenes

- Pyroxenes make up a very important group of minerals

- They occur in igneous and metamorphic rocks

- They are key to identifying gabbro, norite, basalt, several ultramafic rocks

- They are key to identifying high-grade metamorphism (granulite facies, eclogite)

- It is imperative that you can distinguish your pyroxenes

- In general, high relief minerals, bright interference colors, and reasonable cleavage are distinctive

- Two cleavages at almost 90 degrees

- Always check sign (cpx mostly positive, except acmite; opx usually negative, except pure enstatite)

- Always check extinction angle (opx versus cpx)