pyribole

Pyribole is a term used in mineralogy to describe a group of minerals that are either pyroxenes or amphiboles, or both. These minerals are classified as inosilicates, meaning their structures are formed by one-dimensional chains and bands of linked SiO₄ tetrahedrons.12

Pyroxenes are single-chain silicates, while amphiboles are double-chain silicates. Both groups share similar cations and exhibit comparable crystallographic, chemical, and physical properties. However, amphiboles contain hydroxyl radicals, which generally result in lower specific gravities and refractive indices compared to pyroxenes. Their crystal habits also differ, with amphiboles forming needle-like or fibrous crystals and pyroxenes appearing as stubby prisms. Pyroxenes are typically found in high-temperature igneous and metamorphic rocks, crystallizing at higher temperatures than amphiboles.2