I've read about feeding egg shell back to the layers instead of oyster shell. But i've never seen anyone mention using the blender. Then it finally dawned on me yesterday. Use the blender! This is the shells from about six months worth of eggs we've used in the kitchen for cooking and baking. When my jar fills up, i boil them, rinse them, dry them in the oven and crush them. But today i took everything i've been saving and pulverized it in the blender. I'm very happy with the results. This jar is quite heavy. It's coming out kind of the consistency of d.e., so you have to let it settle before you open the blender. Pretty dusty. If i weren't planning to feed this to them when they get to be laying age, i would mix it in the bedding like d.e. Of course, i have no idea if it would help with pests, but it seems like it would be a great drying agent.