Grunerite is an iron-rich mineral belonging to the amphibole group. Its green color and fibrous texture make it a popular gemstone, and it is also used in industrial applications such as asbestos insulation. Synonyms for grunerite include amosite, brown asbestos, and cummingtonite. These minerals have similar chemical compositions and physical properties as grunerite, but may vary in their color, texture, and toxicity. Asbestos minerals, including grunerite, have been linked to serious health risks, such as lung cancer and asbestos-related diseases. Therefore, it is important to handle these minerals with caution and follow appropriate safety guidelines.