nearly all fronts are lost in sedimentary stone
sedimentary is rock. shale is clastic_sedimentary_rock. sedimentary_clay is soil. limestone is sedimentary_rock. clastic_sedimentary_rock is sedimentary_rock. grounds is sediment. slate is sedimentary_rock. sedimentary_rock is rock. shale is sedimentary_rock. sedimentary_rock is stone.