1. Cut the bone through the general area that you want to examine. If necessary, use sandpaper to grind the cut surface flat. The acetate peel technique relies on a chemical difference between a fossil and its matrix-- the rock that surrounds and fills the fossil. The procedure described here works for bone in a limestone matrix.	bone before cutting
	cutting the bone

2. Polish one of the cut surfaces on a glass plate with a small amount of fine grit and water.

polishing the bone

3. Rinse the polished bone to remove any remaining grit.

4. Etch the cut surface by dipping it in a shallow dish of dilute hydrochloric acid for 10 to 30 seconds. The etched surface is now extremely fragile and must be treated gently. If is accidentally touched, rinse it and repeat steps 2 through 4. The acid dissolves the matrix (light gray) faster than the bone (black). This leaves the bone standing in ridges on the etched surface . The etched surface is now very fragile and must not be touched.

5. Gently rinse the polished surface in water to remove the acid.

6. Dry the bone in a sandbox under a lamp. This illustration shows what the acid etching does. The matrix (gray) has been dissolved, leaving the bone (black) exposed and surrounded by air.

7. Squirt acetone on the polished surface. Make sure the bone is not too hot. The acetone flows into the spaces etched out by the acid

8. Before the acetone dries, lay a piece of acetate on the wet polished surface. Do not press the acetate down‚ simply let it settle on the acetone covered bone. The acetone dissolves the acetate sheet, and pulls the dissolved acetate into the spaces around the exposed bone. When the acetone dries off, the exposed bone is left embedded in the acetate sheet. When the acetate sheet is pulled up, the embedded bone remains embedded.

9. Let the acetate dry completely. This will take from 5 to 20 minutes, depending on the size of the bone. There should be no detectable acetone smell.

10. Gently peel the acetate away from bone. You can make as many peels as you like from the same bone by repeating steps 2 through 9. The peel is now ready to be examined. The peel can be mounted between two glass slides using masking tape. This flattens and protects the peel. The peel can also be put between two fresh acetate sheets cut to the right size, and mounted in a photographic slide holder. The slide can then be projected.

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