Changing Planet

The Importance of Silly Putty in Paleontology

Emily Hughes brings us tales of adventure and discovery from the Australian Outback as she and her mother search for unbelievably ancient fossils. Here, she describes the tools of the trade.

Silly putty: it bounces, it stretches, and it’s perfect for making molds of ancient fossils. That, along with other useful tools such as scrub brushes like the ones in your kitchen, dental picks (as in what the dentist uses to scrape the plaque off of your teeth), and good-old-fashioned H2O are the major paleontological tools we need when we are out in the field.

Here is Silly Putty at its finest: displaying the grooves and curves of an ancient marine fossil. (Photo by Emily Hughes)

You might be wondering why we don’t use fancier high-tech equipment. Well, it turns out everything we need to map our Australian rocks and fossils is available to us in most stores (minus the dental tools). We use these because they work really well, they’re easy to find, and it’s fun to see the clerk’s face when we check out in a store with 20 scrub brushes and 10 pounds of Silly Putty.

When the sun is right, Silly Putty can help us see the segments and outline of fossils such as this dickinsonia. (Photo by Emily Hughes)
When the sun is right, Silly Putty can help us see the segments and outline of fossils such as this dickinsonia. (Photo by Emily Hughes)

The brushes and picks are important because when fossils are excavated from the ground they are covered in dirt and grime. Obviously, we can’t study them like that. First we wash and brush the bulk of the dirt away. Then, we use the dental tools to scrape off the excess or hard gunk that’s stuck on.

Once the fossil is clean, we can examine its details in the ground briefly, but to be able to look at it from more angles, more comfortably, in better light, or for a longer time back in the lab, we need to make a cast. In some contexts, that can require great quantities of wax, plastic, plaster, or other substances and equipment. For us, it just requires a bit of Silly Putty. The substance’s ability to instantly take on the form it’s pressed against makes it quick and easy to use. Its fine smooth texture makes for a high-resolution imprint catching all the important details (and many we might not have noticed in the ground), and its relative firmness makes it durable enough to survive handling, touching, and transport. And of course if you don’t like the one you just made, just roll it up and try again. Waste not, want not.

Today, we are excavating a new bed, and all of our fantastic tools will be necessary. It’s a beautiful day, the sun is shining, and we are excited about what we may find beneath the dirt and grime.

Read More by Emily Hughes

Emily Hughes is an undergraduate student at Wesleyan University, born and bred in Riverside, California. She has spent the majority of her summers exploring the Australian Outback, and finding, recording, analyzing and generally admiring the 560-million year old Ediacara fossils preserved there. She is a prospective double major in English and Earth and Environmental Science, and she works for the student newspaper as well as the sustainability office.
  • Grant V. Rasheed

    Congratulations Emily. what a great 1st blog. Thank you for showcasing your perspective of our ancient land, your love for it shows through ! what a great Mother and family you have !

  • Matthew Hamblin

    Wow! I never realized the usefulness of silly putty in Paleontology! That is quiet interesting I have to say!

  • rembo

    OK, but Silly Putty MELTS into a slick. featureless puddle if left alone, yes? So please tell us the next step(s) in the process so we don’t wind up with a drippy mess of plastic putty when we try to make our next priceless casting in the field. Thanks!

  • Emily Hughes

    In reply to Rembo from Jersey, unfortunately Silly Putty only works as a temporary mold of the fossil, which we use to further see the details of the particular fossil, and make a quick replication of how it would have actually looked. It does not work as a permanent cast. For that, we use orthodontic material. If you ever had braces, it’s the stuff they put in your mouth to make a mold of your teeth. Good luck with all your molding and casting adventures!

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