The sand deposits at Burythorpe were deposited back in the Jurassic period (160mya). At the time, this area of Yorkshire was covered by a shallow sea on the southern margin of the Cleveland Basin (an important sedimentary basin of deeper water), and to the north of an area underlain by a granite body known as the Market Weighton High which remained relatively stable throughout the period in contrast the Cleveland Basin which was subsiding.
Reworking and winnowing of the quartz sand in a tidally influenced setting resulted in its high purity and uniform fine grain-size which make its properties so unique in the region and an ideal foundry sand. Occasional storm events deposited shell fragments, including sparse ammonites as lag deposits. An unusual feature are the massive sandstone concretions, some weighing over twenty tonnes which occur sporadically through the deposit.