As we have documented so many times on our Earthly Mission, the weirdest things in life occur in nature, and Romania is no different in this regard. Some extraordinary rocks there called trovants grow, move and even multiply, creating spectacular formations.

The small town of Costesti is home to some really peculiar geological manifestations – the growing stones of Romania. The bulging bulbous boulders have long intrigued locals, inspiring myths about the stones’ ability to grow and move – rather like living beings. Turns out, those legends are actually true.

Researchers suspect the irregular spheroid shapes were formed by the unusually long-lasting and intense seismic activity of the Middle Miocene. The shockwaves created by huge earthquakes compacted the sandy sediments and concentrated the limestone cement in spherical lumps. As the elements wore away over time, the looser sandstone around these lumps, exposing the denser trovants. (Not always though. Of the 100s of known trovants, seen across at least 20 sites through Romania, some were only unearthed after the sand around them was quarried away.)

But what makes these rocks grow, move and multiply?

Trovants are made up of a hard stone core and sand or gravel forming around it. These unique structures can only form in highly-porous sand accumulations and sandstone deposits that are cemented by waters rich in calcium carbonate.

Calcium carbonate is essential in forming a trovant, and it also has a key role in making the rock grow when rainwater is present. After every heavy rain shower, trovants absorb the rain’s minerals, which then mix with the chemicals already present in the rock, creating a reaction and pressure inside. This pressure makes the stone grow from the center to its margins and multiply, with a deposition rate of about 4-5 cm in 1000 years.

Trovants usually have smooth and edgeless shapes and can be cylindrical, spherical or nodular, for example. Irregular cement secretion is responsible for the stones developing these inconsistent shapes as they grow and multiply, and the same is true for their size – it varies from a few millimeters to as large as 10 meters.

But it is not only their structure and ability to grow and multiply that makes trovants unique. They can also move from one place to another. And if that wasn’t enough, they also sport root-like extensions and age rings visible when you cut the stone. However, science still has to explain these unique features.

Since trovants clearly combine the characteristics of a plant and a rock, it’s unclear whether they should be categorized as living or non-living creatures. But whether they are alive or not, these growing stones offer a majestic sight – a must-see when visiting Romania’s Valcea County.