Sunstone, discovered by mineralogists in 1837, is primarily composed of oligoclase from the plagioclase series. Initially, it was very expensive due to its rarity, but it became more widely available after new deposits were discovered in Norway and Siberia. Its name comes from the fact that when viewed from a certain direction, the gemstone will shine with a bright golden brillience, which is a phenomenon known as “Aventurescence”. This shimmer is due to the presence of fine mineral inclusions within the gemstone, such as chalcopyrite, native copper, annite, goethite or hematite, which reflect golden to brownish-yellow light. The color of the gemstone is influenced by the amount of inclusions; the more inclusions it has, the deeper the color. When selecting sunstone, it is best to choose one that is evenly covered with metallic shimmer. To maintain it, avoid impacts to prevent damage along the cleavage planes.