The mural dates back to Sainsbury's opening day in Bexhill on June 8 1976.
The concrete mural, which spans a number of recessed arches on the outside wall of the supermarket, was created by Colchester artists Henry and Joyce Collins. It depicts symbolic icons from the Norman invasion of 1066, including a ship and gold coins bearing the image of William the Conqueror.
It also contains stylised suns, and sea images, including fish, shells and an anchor, as well as a traditional Sussex fishing boat.
The restoration project was completed by Bexhill Heritage volunteers who faced a number of challenges. Having sought advice from Orbis Conservation based in London, who worked on the other murals from the same artist, it was advised to avoid the harsh use of chemical products and to use de-ionised water, washing-up liquid and brushes for the initial cleaning.
It was found the soap began drawing out black oils from the concrete caused by years of being exposed to road traffic. To combat this they treated each relief with poultice, an absorbent paste which, when left on for 48 hours draws out much of the staining.
The original colours had badly faded and volunteers matched the original painting scheme wherever possible. A white undercoat was applied, followed by a base yellow colour then gold mica powder and exterior varnish mixed to create a gilded look.
To help stabilise and protect the plaster behind each panel, they applied three coats of lime-wash paint. This a traditional, eco-friendly coating made from limestone and water.
A wax coating has been applied to the blue part of the mosaics to help protect them. A local trader has offered to replace the missing tiles at the bottom of the mural.
Bexhill Heritage said: “We would like to thank all those who passed by for the kind comments.
The restoration is in memory of former Rother District Council planning office David Beales, who in 1974 and requested the wall to be uplifted to the benefit of the public.
The official unveiling, including a new interpretation board, takes place on Friday October 18 at 10am and all are welcome to come along.
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1. Restoration of the Sainsbury's Concrete Mural by Bexhill Heritage.
Restoration of the Sainsbury's Concrete Mural by Bexhill Heritage. Photo: staff

2. Restoration of the Sainsbury's Concrete Mural by Bexhill Heritage.
Restoration of the Sainsbury's Concrete Mural by Bexhill Heritage. Photo: staff

3. Restoration of the Sainsbury's Concrete Mural by Bexhill Heritage.
Restoration of the Sainsbury's Concrete Mural by Bexhill Heritage. Photo: staff

4. Restoration of the Sainsbury's Concrete Mural by Bexhill Heritage.
Restoration of the Sainsbury's Concrete Mural by Bexhill Heritage. Photo: staff