Tanzanian Sunstone, 18.53 carats

Technical details: Type: Tanzanian Sunstone Weight: 18.53 carats Shape: Cushion Color: Gray Clarity: Unclassified Transparency: Translucent Hardness: 6.0-6.5 Treatment: Untreated Origin: Tanzanian Certification: Electronic certificate (PDF) from Saudi Laboratory (MT) - website (www.mtgl.com.sa) Sunstone is a gemstone belonging to the feldspar group, known for a distinctive optical phenomenon called "Aventurescence," where a bright flash or metallic luster appears inside when the stone is moved. This effect is attributed to small inclusions of hematite, goethite, or sometimes copper, which reflect light. The color of sunstone usually ranges between orange, red, golden, or yellow-green, and can be transparent to translucent. This stone forms in igneous and metamorphic rocks.