1. Plural of actinolite; a green or grayish-green mineral of the amphibole group, commonly found in metamorphic rocks.
Usage: technical; mineralogy

Examples

• The geologist identified actinolites in the thin section of the metamorphic rock.
• Actinolites are often found in schist and other foliated metamorphic rocks.
• The presence of actinolites indicates that the rock formed under moderate temperature and pressure conditions.
• Actinolites belong to the amphibole mineral family and contain calcium, magnesium, iron, and silicate.
• The green color of actinolites makes them useful for identifying certain metamorphic rock types in the field.