This is 2 pound bag of eggshells. Eggshells are natural and rich in calcium and magnesium. They have many uses such as: Calcium supplement for dogs – eggshells act as a binder to rid the body of excess phosphorus which affects the dog's kidneys. A natural way for feeding calcium and magnesium to plants in the garden Boosts calcium and magnesium in the soil for tomatoes and other garden vegetables Boosts calcium in potted plants – as an alternative to using commercial fertilizers Aquarium shrimp and snails love eggshells to supply calcium Magnesium in eggshells boosts plant chlorophyll for photosynthesis A feed source high in calcium for chicks and chicken – preferred over oyster shells Boosting calcium in the compost pile. These eggshells are triple rinsed, crushed, sun-dried and ground by an electric motor to ensure they are fine and lighter for ease of use and application. These are not powdered eggshells. Eggshells contain 90% calcium, 6% magnesium, and 1% phosphorus