The geode of Pulpí
In december 1999, members from Madrid’s Mineralogist Group discovered Pulpí’s Geode in Mina Rica, a colossal mineral geode measuring 8 metres length times 2 metres height fully covered in huge gypsum crystals. It’s upholstered with gypsum crystals, some of them measuring 2 metres long. Its transparency and spotlessness make it a wonder of nature. Given its dimensions as well its crytals size, transparency and perfection, this is a unique phenomenon worldwide (Calaforra & García-Guinea, 2000).
The origin of this outlandish geode can be explained in two stages: the gap formation and the subsequent mineral deposit on the inside. The gap was produced by dolomite karstifications that make up the Sierra del Aguilón, accompanied hidro-termal volcanic shots. The mineral deposit could follow a mixed model (Karstic and hidro-termal).
From the geo-heritage viewpoint, Mina Rica holds many elements of interest besides its gigantic geode and mineralogy. From the structural viewpoint we can observe: foldings, mylonites, fault line surfaces, etc. Furthermore, we can see several formations such as epsomites and calcite speleothemes, mineral neoformations like “gypsum beards”, etc. It’s also worth pointing out the presence of mineralised siderite seams and the differences within the mine lithology. Nonetheless, the most remarkable elements are the gypsum geodes, besides the Gigantic Geode we can also see The Broken Geode and the Swallow Tails Geode among the most peculiar ones so far discovered.
La Sierra del Aguilón has been a mining area all throughout history. Contemporary mining begins in 1840 with the use of trenches and silver galena cuts. After 1870, iron extraction starts taking place, which led Jaravia to become one of the most prosperous mining districts in Spain. During the last decade of the 19th century the Marín Menú Family regenerates the iron extractions from the mine “Quién Tal Pensara” (“Who Would Have Thought It”) and therefore keeping everything going for several decades more until the Spanish Civil War breakout, which led to the full abandonment of the premises. Although it seemed as if Mina Rica was forever forgotten, in december 1999 it gains back popularity thanks to the discovery of the largest mineral geode in Europe. 20 years later, Mina Rica’s reopening project begins in order for everyone to appreciate the wonderful heritage Pulpí’s miners left us with.
All texts from the official website of the geode of Pulpí.