Quartz Cluster with Cassiterite and Pyrite – Yaogangxian

Yaogangxian Quartz Cluster: Discover the exquisite beauty of this rare quartz cluster featuring stunning cassiterite and pyrite crystals. Sourced from the renowned Yaogangxian mine in Hunan Province, China, this specimen reflects the unique mineralogical diversity of one of the world's most prolific mineral localities. The quartz crystals exhibit a hexagonal crystal system, characterized by their high transparency and vitreous luster, with a hardness of 7 on the Mohs scale. Intergrown with these are elongated, deep black cassiterite blades (SnO₂), known for their orthorhombic system and adamantine luster, as well as brilliant golden pyrite crystals (FeS₂) displaying their characteristic cubic form and metallic luster.

Visually, this specimen presents a compelling contrast between the clear, prismatic quartz and the dark cassiterite blades, accented by the warm metallic gleam of pyrite inclusions. The delicate balance of these minerals creates an engaging aesthetic that appeals to collectors focused on crystallography and mineral associations. The Yaogangxian mine is celebrated for producing specimens with exceptional crystal quality and complex mineralogy, making pieces like this highly desirable for both display and study.

Due to the natural fragility of the quartz points and the intergrown crystals, careful handling is recommended. It is best to clean the specimen gently with a soft brush and avoid exposure to harsh chemicals or prolonged direct sunlight to preserve its natural luster and structural integrity.

Yaogangxian tungsten mine, Hunan, China — premier modern source of collector-grade fluorite with quartz overgrowths and purple windows.