Coca, the source of natural cocaine, is one of a handful of shrubs in the Erythroxylum family of plants. Erythroxylum includes over 100 different species of trees, shrubs and sub-shrubs native to South America and elsewhere. Two of the South American species, E. coca and E. novogranatense, have potent alkaloids occurring in their leaves, and those leaves have been used for their medicinal and hallucinogenic properties for thousands of years.
E. coca originates from the montaña zone of the eastern Andes, between 500 and 2000 meters above sea level. It was probably domesticated first: the earliest archaeological evidence of coca use is in coastal Ecuador, ca 5000 years ago. Whether the presence of highland coca in coastal areas means the plant was domesticated at this time, or merely traded, no one has speculated on. E. novagranatense is known as "Colombian coca" and it is more able to adapt to different climates and elevations; it shows up in northern Peru beginning about 2000 BC.
The ancient method of Andean cocaine use involves folding coca leaves into a "quid" and placing it between the teeth and the inside of the check. An alkaline substance such as powdered wood ash or baked and powdered seashells is then transferred into the quid using a silver awl or pointed tube of limestone. This method of consumption was first described to Europeans by the Italian explorer Amerigo Vespucci, who met coca users when he visited the coast of northeastern Brazil, in AD 1499. Archaeological evidence shows the procedure is much older than that.
Coca use was part of ancient Andean daily life, an important symbol of cultural identity in ceremonies, and used medicinally as well. Chewing coca is said to be good for relief of fatigue and hunger, beneficial for gastrointestinal illnesses, and said to ease the pain of dental caries, arthritis, headaches, sores, fractures, nosebleed, asthma, and impotence.
Chewing more than 20-60 gm of coca leaves results in a cocaine dose of 200-300 mg, equivalent to "one line" of powdered cocaine.
Coca Domestication History
The earliest evidence of coca use to date is from a handful of preceramic sites in the Nancho Valley. Coca leaves were direct-dated by AMS to 7920 and 7950 cal BP. Artifacts associated with coca processing were also found in contexts dated as early as 9000-8300 cal BP.
At roughly the same time, coca use is in evidence in caves in the Ayacucho valley of Peru, within levels dated between 5250-2800 cal BC. The earliest evidence of use was identified from deposits in ceramic pots from the Valdivia culture in coastal Ecuador (ca 3000 BC). Evidence for coca use has been identified from most cultures in South America, including Nazca, Moche, Tiwanaku, Chiribaya and Inca cultures.
According to ethnohistoric records, horticulture and use of coca became a state monopoly in Inca civilization, about AD 1430. The Inca elites restricted use to nobility beginning in the 1200s, but coca continued to widen in use until all but lowest classes had access at the time of the Spanish conquest.
Archaeological Evidence of Coca Use
- Nanchoc valley sites (Peru), 8000-7800 cal BP
- Ayacucho valley caves (Peru), 5250-2800 cal BC
- Valdivia culture (3000 BC) of coastal Ecuador (may represent long-distance trade or domestication)
- Peruvian coast 2500-1800 BC
- Nazca figurines (300 BC-AD 300
- Moche (AD 100-800) pots illustrate a bulging cheek, and coca leaves in gourds have been recovered from Moche tombs
- Tiwanaku by AD 400
- Arica, Chile by AD 400
- The Cabuza culture (ca AD 550) mummies buried with coca quids in their mouths
In addition to the presence of coca quids and kits, and the artistic depictions of coca use, archaeologists have used the presence of excessive alkali deposits on human teeth and alveolar abscesses as evidence. However, it isn't clear whether abscesses are caused by coca use, or treated by coca use, and results have been ambiguous about using "excessive" calculus on teeth.
Beginning in the 1990s, gas chromatography was used to identify cocaine use in mummified human remains, particularly the Chirabaya culture, recovered from the Atacama Desert of Peru. The identification of BZE, a metabolic product of coca (benzoylecgonine), in hair shafts, is considered ample evidence of coca use, even for modern day users.
Coca Archaeological Sites
- San Lorenzo del Mate (Ecuador), 500 BC-AD 500, adult male interment with excessive calculus deposits on his teeth, an associated decorated shell spatula and a small bowl-like deposit of an alkali substance (probably once in a gourd)
- Las Balsas (Ecuador) (300 BC-AD 100). Cal receptacle
- PLM-7, Arica site in coastal Chile, 300 BC, coca kit
- PLM-4, Tiwanakoid sites in Chile with a bag full of coca leaves
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