Trovants: The enigmatic Romanian rocks that grow and move 

We all know that rocks are static, non-living beings. But there are some rocks which seem to be ‘living’. Yes, you read that right. Here, we are talking about trovants, rare boulders found in Costesti, Romania. Locals claim that these rocks can expand and shift and seem to be alive! The word trovant, which means ‘cemented sand’ in English, is a synonym for the German word ‘Sandsteinkonkretionen’. Read on to unravel the mystery of these rocks.   

The formation of trovants 
Scientists believe that the extremely rare trovants of Romania were created under very complicated conditions. They were formed after paleo-earthquakes in the Precambrian era, the entire geologic period prior to 600 million years ago. In addition to earthquakes, sand particles from rivers and rain have also played a role in their formation. Trovants can only be created when sand builds around a hard rock base in sandstone deposits. The layers of sand on the rocky base are solidified by water containing a high content of calcium carbonate.  

Do they really grow? 
Trovants absorb minerals from the rain. These minerals catalyse a chemical reaction that results in the formation of layers of sand and sandstone on the rock’s outer region. These layers put tremendous pressure on the trovant, which causes the trovant to expand from its centre towards the outer regions. Thus, these rocks were aptly named ‘the growing stones’ based on how deposits on their surface make them grow in size.  

Do trovants move? 
Yes, they can. This is another interesting feature of these Romanian rocks. You’ve probably heard of the shifting rocks of the Death Valley. Well, if you enjoy studying about mysterious rocks, you should learn about trovants too. Even though they move extremely slowly, trovants do travel some distance. What happens is that when it rains, these rocks absorb the nearby sand. These layers of sand deposits grow in the direction of the waterflow; and as a result, it appears that the rocks are moving. However, they do move only over short distances over long periods. Trovants are an interesting rock type that have gained popularity as a tourist destination in Romania. To further conserve these rocks, the Trovants Museum Natural Reserve was established in 2004. The rocks are so exceptional that the United Nations Educational, Scientific and Cultural Organization has taken over their protection! 

Trovants look like bubbles 
Trovants generally have a smooth and spherical exterior. They almost resemble bubbles, and some even have platforms that look like they are rising from a root system. Additionally, there are numerous ringed, oval layers inside these geological formations. These result from the rocks’ ability to develop by bubbling outside when it rains. They continue to ‘grow’ slowly over the years under certain circumstances, absorbing additional sand deposits from their surroundings. Hence, they look like bubbles.