Linda, you are very welcome! It's been a long time since I've crushed eggshells for the backyard birds ... as I get older, I get lazier.
In my tip, I forgot to include information about baking the eggshells before crushing them. It's a good idea to bake them (250ºF) for five or ten minutes and then letting them cool before crushing them. I have done it without baking but they should be cleaned thoroughly first.
