Collecting a Fossil: The Process Cont.

Creating a Plaster Jacket

In order to transport the fossils from the quarry to the Museum they must be jacketed in plaster in order to protect them along the way. The jacketing process has a number of steps which include: Trenching, Pedestalling, Applying a Separator, Jacketing, Burnishing, Flipping, and Transporting to a vehicle. 

Trenching & Pedestalling

In order to define the boundaries of a jacket a trench is dug all around the area to be jacketed.

In order to be able to flip and remove the jacket, it must be pedestalled. This means that the base of the jacket needs to be thinned.



Applying a Separator, Jacketing & Burnishing

A key step in the jacketing process is applying a separator layer. This usually consists of newspaper, pages of telephone books, etc. that are moistened and applied to the area being jacketed. This protects the bones from becoming directly attached to the plaster jacket. 


During jacketing, wet burlap is placed in wet plaster and then applied to the separator as tightly as possible. Depending on the size of the jacket many layers of plaster and burlap may be needed.

To further strengthen the jacket, additional layers of wet plaster are applied to the jacket and smoothed. This also prevents sharp edges that could cut those handling the jacket. This is known as burnishing.


Flipping & Transporting

Flipping the jacket is the most critical point of jacketing. Without a strong jacket and a good flip all the fossils inside the jacket could be destroyed. Flipping usually requires as many people as possible using a variety of tools including crow bars, picks, shovels, and their bare hands.


Once the jacket is safely flipped the fun isn't over. Now the jacket must be brought to a vehicle to be transported back to the Museum.





Preparing the Fossil

Once a jacket has been collected it needs to be prepared to see what's inside. Preparation is done by highly trained preparators and skilled volunteers. Preparation takes patience, a steady hand, patience, and the right tools. Preparators can work for months or even years on a single project. However, without such preparation the fossils could not be studied or displayed.


Displaying the Fossil

Once fossils have been prepared they are ready to be studied or displayed. The fossil to the left is a Seismosaurus pelvis on display in the Jurassic Hall.





**The New Mexico Museum of Natural History and Science (NMMNH&S) reminds you that if you find a fossil please do not try to excavate it yourself; contact us. Collecting fossils is a rigorous process that takes experience and should only be attempted by experienced individuals.**


<< Previous Page