Monazite-Ce (color change "butterfly" twins)

Item Description

A lot of Monazite specimens are found in granitic pegmatites, but about 15 years ago (2003), there was a discovery of some fine quality Monazites (specifically Monazite-(Ce)) in the hydrothermal tin veins at the world famous Siglo XX Mine in Bolivia. It's noteworthy that these specimens are Monazite-(Ce) as there is an absolute absence of Thorium at this locality, and Thorium is typically a trace element in Monazite species. This piece is a wonderful cabinet sized specimen featuring a richly crystallized vug featuring dozens upon dozens of superb quality, beautifully well-crystallized, rare, very sharp, lustrous, translucent, "butterfly" twinned crystals of Monazite-Ce measuring up to a a full 6 mm (!) sitting on Quartz crystals on host rock matrix. One rarely sees Monazites of this size, color and quality from Bolivia. In most lighting, these crystals show a wonderful pinkish-orange hue, but they actually show a distinct color change depending upon the light under which they are viewed. You can see from the photos that they change from a pinkish-orange to a disticnt yellow hue. This species is often dark and opaque from most localities and rarely bright like the color seen in these crystals. The combination of the twinned crystals, the color, the size (which is very good for the locality) and the overall displayability of the rock make this a VERY worthwhile rarity that would make a superb addition to any collection of rare minerals, Bolivian minerals or worldwide phosphates. Nearly all of the Monazites on this piece are undamaged, but there are a few nicks here and there around the periphery where it was removed from the pocket wall. Valued at $1,500 in the inventory.