Things You'll Need
- Eggshells
- Paper towel
- Oven
- Cookie sheet
- Mortar and pestle, coffee bean grinder or blender
Instructions
Save eggshells from eggs used in your daily cooking or from the eggs you use if you make raw food for your dog. Wash the eggshells under running water and place them on several layers of paper towel to dry.
Preheat the oven to 300 degrees Fahrenheit. Place the eggshells on a cookie sheet and place in the oven for 10 to 15 minutes. This will make the eggshells brittle and burn away any food-grade mineral oil coating applied by the egg producer to protect the shell.
Remove the eggshells from the oven and allow them to cool. Peel any residual membrane from the inside of the eggshells and discard. Use the coffee bean grinder, blender or mortar and pestle to grind the eggshells to a fine powder.