Fluorite from El Filo vein, Durango, Mexico

A rare instance of Quartz replacing Fluorite on a specimen that still has present Fluorites! A remarkable specimen for lovers of pseudomorphs, few of these have ever been found and fewer still survived the years since their discovery.

It is an imposing, heavy, large cabinet masterpiece showcasing a classic Mexican pseudomorph anomaly from the lesser-known El Filo Vein in Durango. Weighing over a kilogram, this significant display piece features an extensive network of blocky, cubic Fluorite crystals that have been masterfully replaced and coated by a sparkling, highly texturized layer of Quartz. The specimen beautifully preserves the distinct "stepped" cubic growth spirals and geometric architecture native to the early El Filo discoveries. The surfaces are heavily micro-crystallized, creating a glittering, sugar-like quartz crust that interacts beautifully with display spotlights. This piece stands out dramatically from typical Mapimí material due to its stable, heavily brecciated silica host matrix and completely unique structural relief.

A pseudomorph is a specimen where one mineral replaces another mineral atom-by-atom, keeping the exact outward shape of the original crystal. When you look at this El Filo Vein specimen, your eyes see the sharp, blocky, square shapes of Fluorite cubes. However, the chemistry has completely changed and the actual material you are looking at is Quartz.