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 Preparing A Dinosaur Bone
The most time-consuming and detailed work in paleontology is the process of making a dinosaur bone look like a bone. What you see in a museum is the result of many hundreds, or even thousands, of hours of work. We aren’t saying that finding fossils is easy, but it may only take a day or two to get them out of the ground and months or even years to prepare them for viewing. This is why there are many more fossils in storage in museum basements and university warehouses than there are on display. In fact, if no more fossils were ever found out in the field, new ones could show up for display for the next hundred years just by using those already discovered and in storage!
The big problem is that most fossils are covered with rock that needs to be carefully removed by skilled scientists called preparators. These people spend most of their work day looking through magnifying glasses attached to their heads and carefully scraping at rocks, trying to figure out which part is rock and which part is fossil. The tools they use are made for working on tiny little spaces, although they are not always designed for use on fossils. Dentists tools are some of a preparators favorites. Small picks, drills and brushes are used. One of a fossil preparators best friends in a type of super glue that holds all the little tiny fragments of a sometimes very fragile fossil together. They also use tiny sand-blasters to remove thin layers of rock and putty to fill in missing pieces. In fact, sometimes there are large parts of a fossil which are never found. This is where the preparator needs to be a talented sculptor to create a missing piece and make it look real.
Ron Stebler is a preparator who lives in Phoenix, Arizona and has prepared fossils for museums all over the world. Ron allowed us to watch over his shoulder as he prepared a bone which came from the back of a Triceratops. This 66 million year old fossil was found in a few large pieces and a number of small fragments. Ron’s job is to make it look like a bone that museum visitors will recognize.
Picture 1
 Here are the three main pieces of the back bone, called a vertebra. Ron has placed them so you can see how they will go together when completed. The top two bones are called a process, the bottom round bone is called a centrum.
Picture 2
 This photo is a close up which shows that the bone is covered with material called matrix. The matrix is the rock or dirt which surrounds a fossil. In this case, the fossil only has a thin coating of matrix so its final shape is pretty obvious. Sometimes matrix is thick and harder than the fossil, which makes it very difficult to remove.
Picture 3
 Here Ron is looking through his magnifying glasses and using a small drill to grind away some of the matrix. This will take many hours of careful work as he doesn’t want to accidentally remove any of the fossil bone.
Picture 4
 Ron has uncovered a small crack in the fossil as he has removed some of the matrix. He uses an eye-dropper to apply glue to the crack. The glue is specially made to absorb into the fossil bone and harden the bone and the surrounding area.
Picture 5
 This photo shows half of the bone with its matrix removed. The color of the fossil is clearly different from that of the surrounding rock. This is because as the bone is changed to stone, it absorbs different minerals.
Picture 6
 With the matrix removed it is time to fill in the missing pieces. Fragments which are lost forever (maybe they ended up in the tummy of T. rex) are replaced with a special putty. Ron’s expert skills mean that even upon close inspection you would never know it wasn’t real fossil bone.
Picture 7
 Ron attaches the top part of the vertebra with glue. In a few seconds, what had been separated for tens of millions of years is now back together!
Picture 8
 A thin liquid which is part glue and part protective coating is applied to the fossil. This will keep it from deteriorating in the air of the museum and protect it from any handling as it is studied.
Picture 9
 This close-up shows Ron’s work on bringing this fossil back to its original shape.
Picture 10
 The top part of the vertebra, or the process, is finished. Now Ron has another week of work to finish the bottom, called the centrum, and attach it to the top – you’ll have to go to a museum to see that!
Now you know how much work is involved and the many steps needed to bring a fossil back to life. And this was an easy one! Some fossils are crushed into hundreds of pieces and are almost impossible to repair. So next time you are at your local museum and admiring a dinosaur skeleton, think about all the time that it took for the preparators to create the wonderful specimen you are viewing.
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