English Lower-Mid Jurassic Limestone

Lower to Mid Jurassic limestones formed in the earlier part of the Jurassic (around 205-175 million years ago). Some commonly used varieties include Doulting, Clipsham and Ham Hill Limestones. The lower Jurassic limestones are generally made up of older limestone fragments which have been re-deposited and therefore tend to be courser in texture and less durable than the Upper Jurassic limestones (such as Portland Limestone) which are more compact