Singular of Andes is Ande.

1. A mountain range in South America running 5000 miles along the Pacific coast.
2. Village in New York (USA); zip code 13731.
Great mountain system or cordillera that forms the western fringe of South America, extending through some 67º of latitude and the republics of Colombia, Venezuela, Ecuador, Peru, Bolivia, Chile, and Argentina. The mountains exceed 3,600 m/12,000 ft for half their length of 6,500 km/4,000 mi.
Geologically speaking, the Andes are new mountains, having attained their present height by vertical upheaval of the entire strip of the Earth's crust as recently as the latter part of the Tertiary era and the Quaternary. But they have been greatly affected by weathering; rivers have cut deep gorges, and glaciers have produced characteristic valleys. The majority of the individual mountains are volcanic; some are still active.
The whole system may be divided into two almost parallel ranges. The southernmost extremity is Cape Horn, but the range extends into the sea and forms islands. Among the highest peaks are Cotopaxi and Chimborazo in Ecuador, Cerro de Pasco and Misti in Peru, Illampu and Illimani in Bolivia, Aconcagua (the highest mountain in the New World) in Argentina, and Ojos del Salado in Chile.
Andean mineral resources include gold, silver, tin, tungsten, bismuth, vanadium, copper, and lead. Difficult communications make mining expensive. Transport for a long time was chiefly by pack animals, but air transport has greatly reduced difficulties of communications. Three railroads cross the Andes from Valparaiso to Buenos Aires, Antofagasta to Salta, and Antofagasta via Uyuni to Asunción. New roads are being built, including the Pan-American Highway.
The majority of the sparse population is dependent on agriculture, the nature and products of which vary with the natural environment. Newcomers to the Andean plateau, which includes Lake Titicaca, suffer from puna, mountain sickness, but indigenous peoples have hearts and lungs adapted to altitude.

Množina: andesites

A dark gray volcanic rock.
Volcanic igneous rock, intermediate in silica content between rhyolite and basalt. It is characterized by a large quantity of feldspar minerals, giving it a light color. Andesite erupts from volcanoes at destructive plate margins (where one plate of the Earth's surface moves beneath another; see plate tectonics), including the Andes, from which it gets its name.