Looking for some information regarding these bricks. My father kept them from t…

Looking for some information regarding these bricks. My father kept them from the Sandgate Gas works during demolition, he worked there since he was a teen. He was told they were shipped in from England early 1800s. I have hit dead end. Brick collectors say they estimate earlier than 1814. At that time the imported bricks were stamped with 2 letters for identification of Quarry or a symbol, a simple Q, pre-dates these practices. Im hoping someone can shed some more light. Thanks.
I will add more photos in comments.