Scientists have discovered that chimpanzees appear to be naturally drawn to crystals, showing a clear preference for shiny, glittering stones and even keeping them in their sleeping areas.
The research explored whether humanity’s long-standing fascination with gemstones and precious minerals might have deeper evolutionary roots shared with our closest relatives, the Chimpanzee.
The study was led by crystallographer Juan Manuel García‑Ruiz and involved nine chimpanzees living at a primate rescue centre. The animals were given access to various stones, including a large Quartz crystal placed beside an ordinary rock of similar size.
While both objects initially caught their attention, the chimpanzees quickly lost interest in the ordinary stone and instead focused on the crystal. They examined it closely, rotating and tilting it to view different angles before eventually carrying it to their sleeping huts.
In further tests, the chimps were able to quickly pick smaller crystals out from a pile of ordinary pebbles. Even when different crystal types such as Pyrite and Calcite were added, the animals still correctly identified the crystalline stones.
Researchers observed the chimpanzees studying the objects carefully, sometimes holding the crystals up to eye level and looking through their transparent surfaces. Some individuals even carried the stones using their mouths, an unusual behaviour that may suggest they were trying to hide or protect the items.
To retrieve the crystals, scientists had to barter with the animals using food rewards, often offering several bananas or yogurt portions before the chimps would give them up.
The findings add to a long-standing archaeological mystery. Crystals have been discovered at ancient sites associated with early humans, including Homo erectus, with evidence suggesting hominins were collecting such stones as far back as 780,000 years ago even though they were not used as tools or jewellery.
Experts believe the attraction could be linked to the unique geometric shapes of crystals. Unlike most natural objects—such as trees, rivers, or mountains—crystals often form symmetrical structures with flat surfaces and straight lines, which may naturally draw attention.
The study’s conclusions remain cautious because the chimpanzees involved had extensive exposure to humans. Researchers say the experiments should ideally be repeated with wild apes, including Bonobo and Gorilla, to determine whether the behaviour appears in natural environments.
The phenomenon is not unique to primates. Certain birds, such as the Bowerbird, are known to collect shiny objects including crystals to decorate their nests and attract mates.
While the study stops short of explaining why humans value gemstones so highly, it suggests that the appeal of glittering stones may run far deeper in our evolutionary history than previously thought.