SiO2 in many beautiful forms! A base of Chalcedony begins our mineralization at the nicely trimmed matrix, forming the center of the Rosette of miniature terminated Quartz, over which are two larger generations of Quartz and Smoky Quartz. A compelling and perfectly presenting small cabinet mineral specimen. Brandberg, Namibia. 3" x 1.75" x 1.75", 4.5 oz.