FLUORITE ON QUARTZ

ABOUT THE SPECIMEN Riemvasmaak fluorite has had a place in the hearts of fluorite collectors worldwide since its discovery in the early 2000’s, and it's easy to see why when seeing their beautiful color and sharp, octahedral form. Aside from the characteristic mesmerizing hues of green within the intergrown fluorite octahedrons, they're laying on a bed of white quartz that serves to elevate the display. Aesthetic combination specimens from Riemvasmaak with both species together have always been the most desirable, and the the form of this one gives it the ability to be displayed well in numerous positions. The octahedrons are in excellent condition, and some very minor edge wear doesn't detract from the high quality of display. As is standard for these  fluorites, they pop out a deep blue under UV.   VIDEO   MORE INFO Riemvasmaak sits roughly 60 km from Kakamas in remote desert terrain between the Orange and Molopo rivers, within the 1.3-billion-year-old Namaqua-Natal Metamorphic Province - specifically the Kakamas zone, a high-grade gneissic terrane flanking the Orange River where fluorite occurs in pegmatites and associated veins. The cause of the vivid green color remains incompletely resolved; geochemical testing documented a suite of rare-earth elements including cerium, europium, and gadolinium in the fluorite structure, and a rare-earth charge-transfer mechanism analogous to that documented at the William Wise Mine in New Hampshire is the leading hypothesis. Crystals form sharp, often gemmy octahedra - occasionally modified by cube faces - frequently associated with drusy quartz or amethyst on matrix, though specimens typically arrived on market encrusted in a sugary secondary quartz coating requiring HF treatment before the fluorite color becomes visible. Locality specimens were known to the Johannesburg Geology Museum from the 1970s, but the material only entered international circulation at Munich in late 2006; a particularly productive window from roughly 2010 to 2013 yielded the finest examples documented. Multiple distinct fluorite occurrences exist within the broader Riemvasmaak area, and loose locality attribution in the trade makes precise provenance within the district difficult to establish for most specimens.