Agatized Algae

The Story

Now that’s a phrase you will not hear anywhere else. Why? Because no one else has ever found these fossils! Here are some of the strangest and most beautiful fossils we’ve ever excavated. We discovered this small site in 2008 by complete accident in the remote deserts of southern Utah while on a canyoneering expedition in the wild. And what a surprise it was! When Vern discovered a few pieces of this material in the bottom of one of the slot canyons we were exploring, we originally thought they were dinosaur coprolites. But further research revealed they are actually colonies of aquatic algae – a discovery that turns out is much rarer. The original algal groups formed knobby, three-dimensional elliptical and spherical nodules on the floor of a shallow sea during Jurassic time, about 165 million years ago. Take a look at the B&W photo here – It shows living algal balls in the bottom of a lake in Ontario, Canada (we took that shot underwater in 2015). Next to it, In Julie’s hand, are two living specimens algal balls from that location. Notice the surface texture of the living forms – they are “bubbly” just like the fossil specimens we’re offering here.

How They Formed
These rare and unique fossils formed when rapidly-accumulating sediment buried the living algal colonies , which then dissolved away and were replaced by quartz.. As the layers piled up, the pressure crushed and distorted most of the spherical algal forms, collapsing their tops downward. In some cases where the crushed ball is still well preserved, there are relic fractures and cracks from the original crushed algae evident. The result is agatized forms with a variety of textures and colors. There’s nothing like these fossils anywhere! As you can see in the site photos, due to the fragility of the original forms, the layers in which these occur yield mostly just fragmentary specimens. Only rarely are the entire algal nodules preserved. NOTE: While some of the agate could lend itself to cutting and polishing into jewelry, we prefer to keep these unique fossil specimens intact.