The presence of small white specks and sometimes very small, unlined vugs. There does not appear to be substantial variation between various samples of Galena Chert.
Texture usually chalky, at least in Minnesota samples.
Sometimes exhibits faint, blotchy mottling. This chert is quite distinctive, however, and would not be confused with other silicates from the Cedar Valley Formation. Thus it seems appropriate to use a separate name. This name has gained wide acceptance, and is given preference here. Several acres of GMC quarries have been identified near the town of Grand Meadow in Mower County.