El Rosario mountain

El Rosario mountain is nestled in La Toma, within the Coronel Pringles Department of San Luis Province, Argentina. This region is part of the Sierras de San Luis, a subrange of the Sierras Pampeanas, located in the center-west of the country. It's about 35 km northwest of La Toma, with coordinates around -32.95213 latitude and -65.69408 longitude, offering a scenic backdrop of mountains and valleys.

The mountain is famous for its green onyx marble, a type of marble composed mainly of calcite, with its green hue likely due to impurities like chlorite or epidote. Other minerals found include aragonite, celestine, and limonite, adding to its mineralogical richness. Geologically, it's a metamorphic rock, formed from limestone, and part of the Pampean Pegmatite Province, which also features igneous pegmatite deposits nearby.

The Santa Isabel quarry, a key feature of El Rosario mountain, has been a source of green onyx marble, possibly dating back to the early 20th century. It's vital for local artisans, with historical mentions of governmental efforts to manage its resources. La Toma, known as the "Capital of Onyx Marble," hosts the National Onyx Marble Festival, reflecting a culture deeply tied to mining and crafting this unique stone.

The climate is classified as Cwa, a monsoon-influenced humid subtropical type, with hot, humid summers averaging 24.0°C in January and cool, dry winters around 8.9°C in July. The Sierras de San Luis boast diverse ecology, with forests and grasslands supporting various species, though quarry activities may impact local habitats.