By: Peter Russell
With the new focus on Earth Sciences in the curriculum teachers are looking for hands-on activities. I have had success with a fossil fish digging activity which has become very popular at gemshows, science openhouses and other events. Mothers and fathers assist their children to extract fossils sometimes for over an hour at a time! I am sure this enthusiasm will be generated for you too.
Fifty million year old fossil fish from the Green River Formation of Wyoming are ideal materials for use in the classroom. I purchase practice pieces of fish fossils from Ulrich's Fossils, Fossil Station #308, Kemmerer, Wyoming 83101 Phone: 307-877-6466 FAX 307-877-3289. The pieces are available at $1.00 U.S. each, plus shipping. Some pieces are easier to work on than others, so it is best to purchase a few extra. The fish fragments are produced as part of the process of collecting whole fish which are prepared for sale and as do-it-yourself kits.
Tools for extracting the fossils may be as simple as a 2" nail or dental tools donated by your dentist or purchased at the surplus store. Brushes to clean away the dust as work progresses and art gum erasers to clean the remaining sediment from the brown fossil bones.
Safety glasses may be worn to protect against flying rock chips. Work on old newspapers or plastic table cloths. It may take a few hours to clean up a fossil. You may wish to set up a table as a paleo lab and have the children work as teams on specimens.
Crumble the sediment to dust by scratching in a small area. Do not chip or flake up larger pieces. Start at a place where you can see brown bones in the layers of sediment. As you scratch away the thin layers of lime mud (micrite), pick up the specimen and smell.... the distinctive smell of fossil fuel (oil)!
If you are interested in working on a whole fossil fish they may be purchased for $20 U.S. and up, plus shipping. The $20 specimens are of Knightia or Diplomystus, two of the most common species. Stronger boned fish such as Priscacara would be a better buy at around $30 if children wanted to prepare one for a science fair project. Many hours of careful work is required to extract these whole fish.
A pocket book with excellent colour photographs of the fossil fish and other plants, animals and insects found in the Green River Formation is titled: "Fossils of the Green River Formation" by Stephano Piccini published by Geolinea in 1997 ISBN 88-87026-06-8. Price, around $10. Order from your favourite bookstore.