This paper analyses the formation of Cenozoic borates in the A rgentine Puna. Various interpretations of the genesis of borates are examined; first, those recorded in primary sources dating from the last century to the present day, and second via data collected in the field. Theories propounding a primary or secondary origin of the Tertiary borates, as well as those that suggest a leaching or thermal origin of playa - lake borates, are discussed.
