You may dream of finding treasure at the bottom of your garden, but Bob Archer has found something beyond price - a 50 million year old rock.
Bob’s rock - a weighty little number with the appearance of a lightly coloured turtle or tortoise shell had been in his garden ever since he and his late wife bought their bungalow home in Catterall Gates Lane some 40 years ago.
But when he enlisted the help of friend Peter Ashfield the mystery of the rock began to unravel.
Bob explained it was suggested he take the rock to Lancaster museum. Deciding it was much too heavy for him to carry he smashed it - revealing a strange mix of stone, glass like rock and other substances - including a soft black material inside.
“I broke it because I thought I’m not going to take it to Lancaster and cart all that - so I just threw it on the floor.”
Lancaster museum staff suggested he take it to Manchester and Bob, aged 86, decided that was just too far to go: So friend Peter stepped in and got a verdict from the University of Central Lancashire.
Now it is hoped part of the rock is to reside at the university and Bob is happy to keep the main piece as a curiosity and to entertain his five grandchildren and two great grandchildren.
Meanwhile Bob, who as brought up at Manor Farm, Nateby and worked with his late brother Jack as an agricultural contractor, has his own theory as to how the rock came to reside in a suburban garden in Catterall.
He recalls that another local contractor called Jack Chippendale used to cart rock off Silverdale beach and take loads to London. Jack’s mate Colin Parker built the house: “Colin would have had a load tipped. I think the rock has come from Silverdale beach..it’s really out of the Atlantic.”
It was Bob’s daughter Mrs Edith Westbury who initially suggested he find out more about the rock. She said: “It fascinates me. It’s just so interesting to think it’s 50 -70 million years old. It’s just an amazing thing.”
Peter, a senior lecturer in business and enterprise at the University of Central Lancashire first sought the advice of a university colleague Dr Joanne Dawson of the Grenfell-Baines School of Architecture, Construction and Environment at the University of Central Lancashire .
After taking a steer from her he carried out more research and prepared a special two page report on “The Catterall Rock” for Bob.
He concluded : “Age wise it was most probably formed in the Cretaceous Period which dates it between 50 and 70 million years old.....”
Peter, who is also a good friend of Bob’s son Stuart, says similar rocks are prevalent in New Zealand. He added: “They are found all around the world...particularly in ancient parts of the seabed. In New Zealand they get quite a few on the beaches.”
Peter’s verdict: “It was probably formed as a result of the periodic volcanic eruptions which killed the smaller sea life which sank to the sea bed and started decomposing.
The minerals in the shells and carcasses attracted sea floor sediments which accumulated around the carcasses and formed nodules or mud balls. When the ocean eventually receded, the mud balls dried out and began to shrink an crack into the beautiful patterns that you see inside the septarian nodules.
Over the eons calcite leeched down into the cracks and formed calcite crystals which grew to fill the cracks, the interface between the calcite and the bentonite clay transformed into aragonite which is the dark brown crystal layer.
The bentonite mud was eventually replaced with limestone which completed the transformation of the entire nodule to stone.”