Found here as the bed rock below Shotley Cliffs, the rock septaria was of economic importance in the area in past times. Septaria was used by the Romans to build Colchester town wall and to produce cement for its construction. There were works producing 'Roman' cement in Harwich, Brightlingsea and Colchester. The cement produced had excellent properties being strong and waterproof.
Uploaded to Geograph by Peter Pearson on 21 April 2013
Photo © Peter Pearson, 21 April 2013.
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