The term 'tomb raider' may well bring to mind glamorous images of Lara Croft or Indiana Jones, but the reality in archaeologically-rich Peru is very far removed. Huaqueros, as they are known, are almost always poor farmers trying to make a little extra cash, rather than organized treasure hunters.
Huaca is a Quechua word meaning an 'ancient temple', 'tomb', or 'funeral mound', of which there are thousands dotted around Peru, left by Inca and pre-Inca cultures. A huaquero, then, is someone who profits from digging into huacas, hoping to find buried treasure.
Not surprisingly, given that huaqueros are disturbing their dead ancestors, usually at night, they are a superstitious bunch. To ward off the malodoro (potentially-lethal gases given off when the tombs are opened), coca is chewed and cigarettes smoked continuously. It is considered madness to work a tomb alone.
Huaqueros are not interested in bones or potsherds, but unbroken ceramics or gold pieces that they can sell on the black market. Unfortunately, in the process of their search, not only are valuable pieces taken, but all sense of archaeological provenance - the context in which the tomb is arranged, for example, which gives invaluable clues as to the status of the person buried - is disrupted.
As such, huaqueros are the bane of archaeologists, who rarely find an untouched grave. However, given the vast number of archaeological sites in Peru, and the limited resources available to explore and protect them, it is fair to say that any of the well-known collections of pre-Inca pottery, such as Larco Museum in Lima or Cassinelli Museum in Trujillo would not be anywhere near as extensive without their efforts.
Nonetheless, it is a practice that is entirely fed by collectors' demand and is not to be encouraged. Peru North urges you not to purchase, if offered an ancient object for sale: they are almost always modern reproductions and even if they are the real thing, it is illegal to take them out of the country.
For a fascinating insight into the world of the huaquero, working around the Temples of the Sun & Moon, near Trujillo, we recommend Hugh Thomson's excellent book, 'Cochineal Red: Travels Through Ancient Peru'.