New study unveils ancient manufacturing techniques behind stone spheroids

In its recent article, Brighter Side features that a recent study has provided groundbreaking insights into the creation of stone spheroids, mysterious artifacts that have long intrigued archaeologists. 

Archaeologists have long been fascinated by stone spheroids, unusual objects found at archaeological sites around the globe.

Dating back as far as 2.5 million years, these roughly spherical limestone objects have been found across regions including East Africa, Europe, the Middle East, and Asia. Despite their widespread occurrence and enduring presence in early human toolkits, their exact function remains unclear.

One of the most notable findings related to these artifacts comes from the Early Acheulean site of 'Ubeidiya, located in the Dead Sea Rift Valley in the southern Levant. Dating to around 1.4 million years ago, this site represents the earliest known evidence of the Acheulean outside of Africa.

At 'Ubeidiya, researchers have uncovered 150 limestone spheroids, offering a rare chance to study these artifacts and better understand their potential role in early human technology and behavior.

The Acheulean period, a phase within the broader Paleolithic era, lasted from approximately 1.7 million to 200,000 years ago. It represents a time when early humans honed their skills in stone tool making, crafting hand axes, cleavers, and various other implements. The spheroids found at 'Ubeidiya, carefully shaped through intentional techniques, highlight the advanced craftsmanship characteristic of the Acheulean era.

For the first time, researchers used advanced 3D mapping and analysis to examine the ‘Ubeidiya spheroids. Led by Antoine Muller, a PhD candidate at Hebrew University of Jerusalem, the team applied spherical harmonics and other geometric metrics to analyze the artifacts’ shapes and surface features.

This innovative method enabled the researchers to quantify the complexity of the spheroids’ geometry and identify patterns in their production.

“Almost all of the spheroids from ‘Ubeidiya, even the nearly perfectly spherical ones, had a flat area on their surface,” explained Muller. “The spherical harmonics analysis helped us identify these surfaces and confirm that this was a repeated pattern, not just in our imagination. These flat surfaces likely served as striking platforms to help shape the spheroids.”

The study, published in Royal Society Open Science, proposes that early humans used a deliberate reduction technique, known as knapping, to craft these spherical objects. Knapping involves shaping stone by striking it with another object to systematically remove flakes.

The researchers suggest that the spheroids represent a sequence of reduction, starting from initial nodules, evolving into polyhedrons, sub-spheroids, and ultimately into complete spheroids.

The implications of these findings go beyond just ‘Ubeidiya. While spheroids have been found at other Lower Paleolithic sites in the Levant, such as Hummal, Latamne, and Qesem Cave, the large sample size and advanced analytical techniques used at ‘Ubeidiya offer unprecedented insights into their creation.

The researchers have made their dataset publicly available online, allowing for further examination and comparison with spheroids from other regions.

By Naila Huseynova