Actinolite is a calcium magnesium iron silicate mineral from the amphibole group, formed under high pressure and temperature in metamorphic rocks. It is commonly found in areas rich in limestone and dolomite. The gemstone is known for its green color range, from pale green to deep forest green, influenced by iron content. It can occur as prismatic, needle-like, or fibrous crystal structures with a glassy to silky luster. Transparent varieties may be cut as gemstones, but most are valued as mineral specimens. Actinolite is also associated with nephrite jade, contributing to its strength and structure. Although not widely used in mainstream jewelry, it is highly appreciated by collectors. It is often linked with balance, grounding, and natural energy.