A fossil was found underneath the Denver Museum of Nature and Science’s parking lot three days ago. It was discovered during drilling for a possible geothermal heating system, a renewable system that uses the Earth’s heat to warm homes or generate power. The drill pulled up part of a dinosaur bone from over 750 feet underground.

James Hagadorn, a scientist at the museum, said finding something like this during that kind of project is almost unheard of. According to the museum, it’s only the third time in the world a fossil has ever been found this way.

The fossil is a vertebra, most likely from a tiny herbivorous dinosaur. Scientists can’t pinpoint exactly which dinosaur it was because of the way the fossil was excavated. The sample came up alone and without the surrounding rock that usually helps give more clues. This is because the rock surrounding a fossil could contain more of that fossil, helping scientists determine what creature the fossil was.

Some paleontologists, like Thomas Williamson of the New Mexico Museum of Natural History, say that while the fossil is interesting, it is not a large contribution to science. Without more bones or rock layers, it doesn’t lead anywhere.

Currently, the bone is sitting in the museum. The staff were excited by the discovery, but said they have no plans to dig under the parking lot again, as they still need that area for vehicles.

This area of Colorado has seen lots of fossil discoveries, but this was a little different because this find wasn’t through a dig or a planned discovery, but rather by chance.