Limestone (rugose coral)

Limestone horn coral

Limestone (fossilerous)

Biogenous sedimentary rock.
This sample of Devonian-age limestone displays a large rugose coral (horn coral) and crinoid column disks (fragments) in a fine limestone matrix. This sample comes from the Falls of the Ohio, Devonian reef area exposed in the Ohio River bed in Louisville, Kentucky. 2/2/2021