Other limestones are also known which contain an admixture of clay.
They occur in limestones and shales and are not associated with igneous rocks.
And what's all this I hear about limestones and butter-scotch and wisdom?
The Cretaceous limestones of Mexico were folded into lofty mountains.
Geologically, it has a basis of limestones, resting on sandstones.
Soft stones, ...