The gods made us from their blood, the Mayas believed, so we were indebted to them at our creation; we returned the favor by making periodic sacrifices of our own blood. A favored tool for these auto-sacrifices was the spine removed from the stingray's tail. This sharp barb possessed spikes that pointed in such a way that once it pierced the skin, it could not pulled out in the same way it had entered without inflicting gruesome damage; the smart thing to do was to keep pushing it through. Mayan men drew blood from their groins. Women could choose either the tongue or the ear as the place where they cut. The blood was dribbled onto paper which was then burned.|
Both the real thing and jade substitutes have been found in Mayan tombs. The spines were usually placed over the groin where they could be easily found by the deceased in the afterlife.