Fossil Hunting! A New Adventure at the State Capitol

To paraphrase Lily Tomlin: This year, our winter has been perverse—it can get warmer, but it won’t. I’ve been looking for things to do—but as you know, I’m not keen on ice, and there’s still plenty of that around.



So we found something incredibly fun to do! But first, you should know a little about the state capitol.

When I was a kid, and my family was visiting Grandma S (who didn’t have a/c), on some hot summer days my brother and I would walk up to the capitol and enjoy its cool, dark, marble hallways. It was like spelunking! It was like a mini vacation!



I still find the capitol a good getaway. It’s a breathtakingly beautiful building. As a public building, it’s ours, and we can go in there. I like to take walks around its pleasantly landscaped grounds, and look north at the train tracks and the river. I like to go inside and visit the museum. I also like to admire the art.

But last weekend, Sue and I had a new kind of adventure at the state capitol!



The winter 2014 issue of Missouri Resources, the magazine of the Missouri Department of Natural Resources, had a neat article in it about the fossils visible in the polished limestone walls and floors of the capitol building.



You need to check this out! The article is “Capitol Fossils,” by Patrick Mulvany. You can see the article online, or (even better, I think), looking ahead to more neat articles, you can also subscribe to the magazine. Subscriptions are free to any Missouri resident (super-cheap for anyone else); you only need to sign up for it, which you can do here.



Why are there fossils in the walls of our state capitol? Well, anyone who took Geology 1 with Prof. Houseknecht at Mizzou should know the answer: it’s because the “marble” isn’t true marble. It’s actually limestone that’s been polished.

Limestone’s a sedimentary rock, which, as we Missourians know, can be chock full of cool fossils. You just walk down a creek bed, picking up rocks, and you can see oodles of fossil echinoderms, mollusks, and other invertebrates. These include crinoids (our official “state fossil”), brachiopods, corals, bryozoans, snails, nautiloids, and more.

These are what’s left of the hard shells and other structural materials of saltwater animals that lived here 335 million years ago, when this area was covered by a sea (in the Mississippian Subperiod, if you want to get technical). Here is what you often find in an Ozark creek bed:









True marble (which isn’t found in Missouri) is a metamorphic rock created when limestone undergoes tremendous pressure and/or heating. Any fossils, impurities, or other interesting inclusions that were in the original limestone lose their shape and are reduced to mere swirly patterns in the marble.

The limestone used to build our capitol is named “Carthage marble” because in the commercial stone trade, this hard, dense, high-quality limestone that can take a decent polish without crumbling is called “marble.” Carthage is the town in southwest Missouri near where this limestone was quarried.

By the way, you can find polished limestone used as architectural marble all over the state. As Prof. Houseknecht pointed out to us, the bathroom stalls in UMC’s Memorial Union south wing are made of polished limestone; he asked us to “go” in there and notice the fossils!

The restrooms at the state capitol are included! You might end up taking extra time in a stall examining the nifty fossils in the partitions! Only ladies are allowed to see this cool nautiloid (or maybe it’s just a snail; but look at the chambers within the coils!):



(Yes, I did! I stood there in a bathroom stall and took a picture!)

Another nautiloid is visible to everyone and is mentioned in the magazine article. This specimen is nearly a foot long! The creature that lived in this conical or cylindrical shell (Gomphoceras sp.?) looked something like a squid, tentacles and all.



So, there are these cool fossils at the capitol that you will miss the first 150,000 times you visit. Naturally, the bigger attractions at the capitol are the majestic architecture of the building itself; the museums; the artwork; maybe even the lawmakers, lobbyists, and other governmental denizens.



But there are copies of a veritable treasure map at the welcome desk. With it, you can hunt all over the capitol for the nifty fossils featured in the magazine article. And, more fun yet, make your own discoveries!



It’s a good idea to bring a flashlight and a hand lens. You’ll look a little funny examining the walls so closely, but really, it’s good for the legislators to see that. It helps remind them that they and their pet bills are not the gravitational nucleus of the universe.



One more thing: I was especially eager to go on this treasure hunt because I wanted to see some examples of a type of bryozoan fossil called Archimedes (the genus is named for the screwlike form that commonly remains of the animal).



I’ve recently educated myself about Missouri’s current, living bryozoan species (read more about Missouri’s living bryozoans here), and now I’m wanting to find all kinds of examples of them—fossilized or living!



(Oh, I’ve got big plans for this summer’s explorations, born out of a long winter’s cabin fever! But more on that later!)