An impossible artifact
In 2008, inside Denisova Cave in the Altai Mountains, archaeologists uncovered two fragments of a stone bracelet. The soil layer where it was found, Layer 11, also contained the first physical evidence of a previously unknown human relative: the Denisovans. Oxygen isotopic analysis of the surrounding soil dated the find to at least 40,000 years ago. Some research suggests it could be significantly older, possibly between 65,000 and 70,000 years old.
The bracelet is made from a dark green chlorite, a mineral not found locally. The nearest known source of this stone is over 200 kilometers away, suggesting the material itself was valuable. The assembled fragments show the bracelet would have been about 2.7 centimeters wide and 0.9 centimeters thick. The object is unusual because is the manufacturing technique. Analysis of a narrow hole, just 0.8 cm in diameter, shows it was created with a high-speed drill. The tool's rotation was fast and its stability precise, creating a perfectly round hole. These techniques, easel drilling, boring, grinding, and polishing,were not thought to have been developed until the Neolithic period, tens of thousands of years later.
Made by mysterious cousins
The bracelet's creation is attributed to the Denisovans, an extinct species of archaic human. Before the discoveries in this cave, Denisovans were known only from their genetic legacy in modern human populations. The bracelet was found in the same geological layer as a Denisovan finger bone, and researchers believe the cave's Denisovan layers were not contaminated by later human activity.
The skill demonstrated by the bracelet changes previous assumptions about the cognitive and technological capabilities of archaic humans. Alongside the bracelet, archaeologists have found other advanced artifacts in the same cave layers, including a marble ring and a 50,000-year-old sewing needle made from bird bone. The bracelet itself shows signs of wear and repair. A polished area near the drill hole suggests a leather strap with a heavy charm was once attached. Scratches on the surface appear to have been sanded down, indicating the owner maintained and repaired the object. In sunlight, the polished chlorite reflects rays, and by firelight, it appears a deep green. Its fragility and beauty show it was not for everyday use, but worn on special occasions.