Very curious specimen of agate from this classic Argentine locality that shows us the characteristic botryoidal shapes that have been slightly polished to show us the beauty of this semiprecious stone. This specimen belongs from the Trigo collection (Mataró) and was acquired at the Mineralexpo Barcelona-Sants mineral show, in Barcelona, decades ago.

Very good sized specimen of rhodochrosite from this classic Argentine locality. In the polished part we can enjoy the characteristic bands, with good color. And the "natural" part tells us that it belongs from a vein. It has a handwritten label attached on the sample and due to its appearance it was a very old piece.

Group of doubly terminated crystals of pseudomorphic hematite after magnetite, elongated and with defined faces and edges. They show exceptional skeletal growths, very marked and partially coated by recrystallizations of small crystals of lenticular hematite. The crystals were formed in the fumaroles of this enormous Argentinian volcano. The Payún Matrú is a large volcano with an intermediate morphological type between a volcanic shield and a stratovolcano, that is located 530 km from the oceanic fosa and marks the subduction zone of the Nazca plate. Currently this area is a national park and collecting minerals is prohibited.

Group of well defined microcline crystals partially covered by minor muscovite and white albite crystal growths. Accompanied by smoky quartz crystals with a uniform smoky tone and transparence.