Brazil is currently the leader in overall production of amethyst. This article describes the author's visits to three of Brazil’s most important mining areas: Marabá, Pau d’Arco, and Rio Grande do Sul ...

During the past 25 years, the corundum market has been transformed from one of medium to high-priced gems to one that encompasses nearly all price ranges. This transformation was caused by the ...

Adjacent amethyst and citrine colors in the same crystal of quartz have been reported from South America, although there appears to be uncertainty as to the exact locality of origin. Such material has ...

The best ametrines show distinct areas of orangy yellow and purple. These colors are featured in this graceful cut design. Photo by Lydia Dyer, © John Dyer & Co ...