In the heart of China’s Guizhou Province, an unusual geological phenomenon has puzzled both locals and visitors alike. Dubbed the "egg-laying mountain," a cliff named Chan Da Ya seems to produce large, round stones. Weighing up to 660 pounds, these "stone eggs" are said to drop from the cliff every thirty years. Despite years of study, scientists remain uncertain about the true cause of this phenomenon.

The Cultural Significance of the Stone Eggs for the Shui People

In the small village of Gulu Zhai, which is home to the Shui people, stories of this mysterious mountain have been passed down for centuries. The cliff, although only six meters wide and 20 meters in length, has sparked the imaginations of those who live near it. Locals eagerly search for these rare stone eggs, hoping to find one freshly fallen from the cliff. These rocks, dark blue in colour and smooth, can range in size from 20 to 60 centimeters in diameter.

The Shui people, who have lived in the region for over a millennium, hold these eggs in high regard. They believe the stones bring good fortune and protection to their homes, animals, and families. Almost every household in Gulu Village owns at least one stone egg. Some of the eggs have been sold or stolen, but about 70 remain in the village.

The Geological Puzzle Behind the Stone Eggs

Scientists believe the stone eggs are ancient, dating back to the Cambrian Period, around 500 million years ago. The Cambrian Period, known for the "Cambrian Explosion," was when most major animal groups first appeared. Geologists theorise that the area around Chan Da Ya was once underwater. Over time, silicon dioxide in the water may have caused the stones to form into spherical shapes. These stones, now metamorphic rocks, have been buried within the cliff for millions of years.

As the calcareous rock of the cliff gradually erodes, the metamorphic stone eggs become exposed. This erosion occurs faster in calcareous rock, which is softer and more prone to weathering than the metamorphic stones. Over time, the eggs fall from the cliff as the surrounding rock wears away. Locals estimate that each egg takes about 30 years to fully emerge.

Though this might seem like a slow process, it has fascinated locals for generations. The falling of a stone egg is considered a rare and lucky event, making these rocks even more precious to the people of Gulu Zhai.

Professor Xu Ronghua of the Chinese Academy of Sciences believes the eggs were formed due to the unique underwater conditions in the Cambrian Period. The spherical shape, he explains, comes from the natural properties of silicon dioxide, which tends to form round particles in water.

Interestingly, the cliff surrounding the eggs is not made of the same material. The calcareous rock is sedimentary, unlike the metamorphic stone eggs. This difference in composition explains why the cliff erodes much faster than the stones. As the cliff continues to break down, more eggs are likely to appear over time.

Visitors who travel to this remote village are often in search of these mysterious stones. Some come out of curiosity, while others hope to experience the wonder of witnessing one fall. But as the mountain wears away, these stone eggs will eventually become a thing of the past, or perhaps find new homes in museums or private collections.

Scientists are still studying this rare phenomenon, but as of now, the true mystery of the egg-laying mountain remains unsolved. Until then, the village of Gulu Zhai continues to celebrate and protect its unique geological heritage.

The legend of the stone eggs lives on, drawing in curious travellers and inspiring awe in those who visit the Chan Da Ya cliff. As the mountain continues to erode, it leaves behind not only these extraordinary eggs but also a story that may last for generations to come.