In 2017, I visited the Messel Pit in Germany, and wanted to make a replica of a backlit bat fossil I’d seen there.
The Messel Pit is a Unesco World Heritage Site, and with good reason: its specimens are incredible. They date to the Eocene epoch, when horses were tiny, (some) birds were massive, and primates were just splitting off from lemurs.
Because of the nature of how these species were preserved in oil shale, incredible amounts of detail have been preserved: skin, fur, even partially digested food. For me, the most amazing specimens were the bats, which are so small and delicate that for them to be preserved at all is near miraculous.
Because of the oil shale’s weak composition, the scientists at the Messel Pit created a method of replacing this shale with an amber-colored plastic, which would 1) better preserve the fossil outside of the pit, and 2) better highlight detail on the specimen. The designers of the Visitor’s Center leaned into this, and displayed every fossil as though it were a work of high art, lit brilliantly from behind. It was one of the most mesmerizing displays of natural history I’ve seen, and I wanted something like it when I came back home.
After Googling, I found a replica Messel Pit bat fossil I could buy online for around $20 from the Prehistoric Store (link). I was excited about the detail, but a little bummed that when it arrived it was all black. I’d have more work to do.
First things first, I made a mold using platinum silicone from TAP Plastics.
My first attempt at making a replica, I used some casting resin that I dyed lightly black, and filled it into the fossil portions of the mold using a paintbrush.
Across the board, this first attempt was too light, but layering the resin with different colors was effective as a technique. I added more dye in future casts.
This time the amber coloring turned out, but the bat skeleton itself was too light.
I designed a box with help from Box Designer. For the design around the bat cast, I traced the outline of the cast in pen, then did my best to add it in Illustrator. In this first version, I etched the caption directly into the bat box—ultimately, I decided to have the caption also be made from amber-colored acrylic.
With an early version of the bat cast, I put together the box design in walnut wood.
Philips Hue light placed inside Bat Box, so that it can change brightness to suit mood / whatever Alexa tells it to do.
Original: too dark, doesn’t resemble the Messel Pit fossils’ display pattern.
Mold
Cast 1: overall too light
Cast 2: Background good, but bat is far too light.
Cast 3: Wayyy overdid it on black for the bat
Cast 4: Final!