I’ve been interested in rocks since I was a kid. Our family would go for rides in the mountains to explore. I’d come home with collections of rocks and crystals in my pockets and on the floor of the station wagon. I remember getting one particularly cool-looking crystal-embedded rock while on a trip to Rocky Mountain National Park. I just started at it like it was a huge treasure. That rock got lost in a family move not long after I collected it. However, it was really inspiring and I remember it after all these years.

How Did a Rock Get Started? It’s a Long Story

One thing that I used to do was look at a rock and think, “Where did you come from?” Of course, the first answer was “the park” or “the mountain”. Then, after learning more about how rocks form, I’d think about the formation process that brought the rock to me. We lived (and still live) on the edge of what was an ocean that existed hundreds of millions of years ago. Eventually (and there’s a long geologic history you can read in the famous Roadside Geology of Colorado), the oceans receded and dried up.

That left behind huge deposits of sandstones. Mountain-building processes pushed up the ancestral Rockies. they eroded away, eventually. Then, another round of mountain formation created the current Rockies. The rocks you find around here can be sandstones and shales, created from deep water deposits and shoreline areas. Or, maybe they’re granites and other rocks formed in conjunction with volcanic activity and the pushing-up of peaks to form the Rockies.

So, the rocks I used to find were probably sandstones. However, the one with the crystals clearly had formed differently from the red rocks I had collected first. And, among the rocks, we’d find fossils and, in some places, we could go and find sharks’ teeth just lying around. So, clearly, the region I grew up in had some history to it.

Everything Starts in Chemical Elements

It wasn’t until college and a chemistry class that I learned about the elements that formed the rocks and crystals I used to collect. A rock that I thought was pretty boring turned out to be feldspar, like the one in the picture here. It’s a common rock, but with an interesting history. If you ever pick one up, you’re holding a collection of elements. They can be potassium, aluminum, silicon, oxygen, sodium, or calcium in varying combinations. And, to get to BE a rock, they had to be part of volcanic activity. That could have been a flow, or when a flow impinged on another rock.

And, actually, feldspars can be found in sedimentary rocks. Those are created as other rocks erode and eventually get cemented together in layers. I won’t get into the technicality here, because it’s a lot. But, the creation of what looks like a simple pebble or rock belies a lot of activity.

Chemical Elements Started Somewhere, Too

The thing to remember is those chemical elements. They all came from someplace here on Earth. However, they didn’t start here. They GOT to Earth because some of them existed in the cloud that gave birth to our star and our planet. And, how did they get in the cloud? Well, they formed in other stars, for the most part. All but the hydrogen. That was created in the Big Bang, nearly 14 billion years ago.

So, that rock you hold in your hand? It came from space. Maybe not directly, like a meteorite, but through a long process. It included starbirth, star death, and wandering in a nebula. Then, it’s elements came together to form protoplanets. They slammed together to make a planet, which then experienced its own evolutionary history.

The next time you pick up a rock, ponder it a while. Think about its journey from space to your hand. and, then, think about the similarities it has with YOU. Because you, too, formed from chemical elements.

And me? I still pick up rocks. I have one rock from nearly every continent on Earth. And, they keep me company as I write about the cosmos from my office in mountains that formed millions of years ago to supply rocks for me to ponder.