Kiawthuite holds the title of the rarest mineral on Earth, with a single confirmed specimen that has drawn attention from scientists and collectors alike. The extraordinary claim was reported by Science Alert and has become a focal point for researchers across geology and mineralogy.
Kiawthuite is a tiny amber-orange gemstone weighing 1.61 carats, roughly 0.32 gram. At first glance it can resemble topaz or amber, but its unusual chemistry sets it apart and makes it priceless.
The journey began when gemologist Kyaw Thu purchased the stone from the Chaung Gyi market in Myanmar in 2010. Initially, he thought the specimen might be scheelite, a common tungsten mineral, but a careful cut revealed something entirely unusual and unexpected.
Kyaw Thu sent the piece to the Gemological Research Laboratory in Bangkok for rigorous testing. There scientists determined that the mineral’s composition Bi3+ Sb5+ O4 had never been seen before in nature.
Inside Kiawthuite there are hollow inclusions that resemble veins. They appear under shear forces and are taken as evidence of a natural origin. Geologists propose that Kiawthuite forms in igneous rocks, especially pegmatites, a class of coarse-grained volcanic rocks where large gemstone crystals develop.
Trace elements were detected: titanium, niobium, tungsten and uranium. Their presence aligns with magmatic cooling processes, yet the exact conditions that create Kiawthuite are believed to require a rare combination of factors, making the mineral a modern mystery for scientists.
The sole known specimen resides in the Los Angeles County Museum of Natural History and is considered invaluable. In comparison, painite, commonly cited as the second rarest mineral, trades at tens of thousands of dollars per carat, with typical estimates around fifty to sixty thousand dollars per carat.
Kiawthuite continues to captivate researchers and gemologists, inviting further study and debate about how such a material forms and what it reveals about Earth’s deep geological processes.
The quest to understand Kiawthuite serves as a reminder that Earth’s inventory still holds surprises and that every rare find opens new questions about our planet’s past and its ongoing geology.