[4] He was considered by Luis Abel Orquera to have been "the principal authority on indigenous Pampean-Patagonian art.

Gradin and his team's study of cave art in and around Cueva de las Manos formed the most important research on the site.

[2][7][8] In his studies, Gradin helped to separate the different stylistic sequences of the cave, and of rock art in Patagonia as a whole.

[8][9][10][11] The importance of his discoveries to the country's natural and cultural heritage resulted in the site being named a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Site in 1999.

[8] Carlos J. Gradin was born in 1918 and died in 2002,[12][13][14] making him 83 years old at the time of his death.