These mushroom stones were discovered in the Maya ruins of Kaminaljuyu in Guatemala. They were used 2500 years ago to prepare mixtures of psychedelic mushrooms for ceremonial use...
https://en.wikipedia.org/wiki/Entheogenics_and_the_Maya
https://en.wikipedia.org/wiki/Entheogenics_and_the_Maya
The consumption of hallucinogenic plants as entheogens goes back to thousands of years. Psychoactive plants contain hallucinogenic particles that provoke an altered state of consciousness, which are known to have been used during spiritual rituals among cultures such as the Aztec, the Maya, and Inca.[1] The Maya were indigenous people of Mexico and Central America that had significant access to hallucinogenic substances. Archaeological, ethnohistorical, and ethnographic data show that Mesoamerican cultures used psychedelic substances in therapeutic and religious rituals.[2]