St Lawrence Church - Norman Stonework?
This Lozenge Fret pattern is Norman so the carving is likely to be from Old Sarum and 900 years old.
More details & Sources are given in the article below.
This article by Kerry O'Connor was previously published in the Friends of St Lawrence Church Newsletter issue no. 34, Autumn 2020 and is reproduced here by kind permission of the Friends. link to Friends page
The Church of Stratford Juxta Sarum. The speculative saga of two stones
If only stones could talk………………….
A pair of ashlar stones in the north wall and a buttress to the south wall of Saint Lawrence church nave just look out of place. They do not look as though they were carved to sit there. They could therefore be from Old Sarum. Old Sarum was the site of an uneasy sword and sandal coexistence. The sword part was use as a military installation and this continued until WWII, the sandal part as a religious institution ended 800 years ago.
A stone in the North wall
(position circled below)
A stone in a buttress on the South wall,
(position circled below)
The stones show two rows of four lozenges. Or rather two and two half lozenges. Perhaps this was part of a heraldic carving. A single lozenge used as a shield denotes a woman. A field of them on a shield was known as lozengy. The Countess (Margaret Pole) and Earl of Salisbury arms had a row of fusils which are “squeezed” lozenges or slightly taller and thinner than lozenges but only three and here we have four per row. The Dinant, Dynham, Dyneham, Denham family arms bore a row of four lozenges and though his ancestry was uncertain Sir John Denham was MP for Old Sarum (one of the two) put there 1661 by the Earl of Pembroke to 1669 when, insane, he died probably of syphilis. But here we have two rows of four not one.
They were more likely an entirely decorative device continued along adjacent stones, perhaps as a cornice or architrave. That on the south wall is better preserved and was likely to be the earlier of the two incorporated into the church. Perhaps it was an inside stone first. It is in the more sheltered site. The northern stone is more weather worn. Rows of lozenges or multiple rows as Diamond or Lozenge Fret mouldings are common features of Romanesque architecture. Lozenges as an example of Norman ornament have been recorded at Old Sarum and stone from there in the current Cathedral Close wall of the North Gate. 
The illustration on the right matches our stones, both have chamfered horizontal bars between the proud lozenges or traversing the negative recessed lozenges in between. “…two sets of oblique lines crossing each other, and then from the centres of the lozenges thus formed cutting away the stones slopingly to the points and thus by lowering one set giving relief to the alternate ones” exactly describes the masonry in these stones. These are dated at 1120 meaning our stones could be 900 years old having lain in their current positions for 500 (south) or 300 (north) years or less.
This is not the first time these stones have been noted. “at least two blocks, incorporated in later masonry, bear Norman ornament, but the date of their incorporation is unknown.” 
If we could hear these stones speak we may hear tales of a thousand years.
11th Century. It is possible these stones were part of the first Cathedral 1075 to 1092, Bishop Osmund, or the Royal Palace where they may have looked down on William the Conqueror. The cathedral fell down in 1092 leaving stones lying around ready for re use. This would mean the stones are early Norman but there is no evidence for this. 
12th Century. These stones are more likely to be later Norman and de novo from the more elaborate and larger second cathedral 1107-1140, by Bishop Roger, or his palace, or again the rebuilt Royal Palace where they may have looked down on Henry I and II. The Norman period of architecture closed with the death of Henry II in 1189. Our stones therefore are likely to date from 1107 to 1189
13th Century. If they were in the cathedral they may only have had a century in use as the cathedral was abandoned in 1220, in favour of the current cathedral. Demolition began soon after. Some masonry was re -used in the new cathedral and close. Removal of these stones probably did not occur before the 13th Century.
14th Century. This south east corner of the nave was built meaning it is possible the stone there came direct from Old Sarum cathedral or palace without an interim resting place. This building was consecrated.
14th and 15th centuries. It would seem more likely that the stone now in the northern wall was in a building than in the ground. It need not have been its original building. There were several churches and chapels around Old Sarum including St Lawrence Juxta Sar’ plus a succession of secular buildings where it may have served.
15th century. The last major rebuild of the castle.
15-16th Centuries, the building of the inner part of this section of the northern wall at St Lawrence nave
16th Century. Henry VIII permitted Thomas Compton to remove and re use stones from the derelict castle, it being “a desolate and barren place and can never be made inhabitable”. 
18th Century is perhaps when the stone came to the northern nave wall as that is when the outer part was built. There were extensive repairs to the church and Thomas Pitt built the tower.  The precise site of the cathedral had been lost over the centuries though its existence was well known.
19th Century, a drought reveals the footprint of the old cathedral
20th Century, excavations at Old Sarum but our stones were in place long before this.
But as we listen all we hear is a stony silence, the masonry is mute, and its history lost.
Photos by the author
 Parker, John Henry. 1850. A Glossary of Terms Used in Grecian, Roman, Italian, and Gothic Architecture Ed 5 Vol 2 ..plate 113
 A History of the County of Wiltshire: Volume 6. Originally published by Victoria County History, London, 1962. Stratford-sub-Castle Pages 199-213
 Parker, John Henry. 1856. A Manual of Surface Ornament. Forming No. 3 of a Series of Manuals of Gothic Ornament page 11
 Henry VIII: December 1514, 26-30', in Letters and Papers, Foreign and Domestic, Henry VIII, Volume 1, 1509-1514, ed. J S Brewer (London, 1920), pp. 1485-1503. British History Online
http://www.british-history.ac.uk/letters-papers-hen8/vol1/pp1485-1503 [accessed 24 May 2020] Pat. 6 Hen. VIII. p. 1, m. 23. [5715.] Grant 29