Snuff Powders from Pre-Hispanic San Pedro de Atacama: Chemical and Contextual Analysis.

The article presents a detailed discussion of the chemical and contextual analysis of snuff powders from the pre-Hispanic time of San Pedro de Atacama. It states that humans since ancient times have used plants not only as sources of food but also as part of their healing practices and rituals. It mentions that in pre-Hispanic times, the river valleys and oases of the Atacama desert of northern Chile were occupied by a succession of preceramic hunter-gatherers and ceramic-stage agriculturists and herders.