Calcium Carbonate grit vs granite grit

[R2elk]

The ingredients is ground limestone. So my chickens are not laying but at 18 weeks are close to laying. Should I wait to use this until they are laying.

They are doing some grazing every other day at a minimum of two hours. Our soil has a variety of sizes of peebles, dirt.

Based on these statements, you should not need to add grit. The stuff in the bags is an acceptable substitute for oyster shell for laying hens.

The company's claims that it is acceptable as grit is an outright lie. Calcium carbonate from crushed limestone is not an acceptable substitute for grit. It is far too soft to aid in grinding food and contains far too much calcium to be used for anything other than a calcium substitute.