metric is a mean of metamorphic stone
gneiss is metamorphic_rock. slate is metamorphic_rock. nanogram is metric_weight_unit. marble is metamorphic_rock. amphibolite is metamorphic_rock. euclidean_metric is metric. metamorphic_rock is rock. metamorphic_rock is stone. marlite is metamorphic_rock. marble is useful_metamorphic_rock.