(Middlesex Filter Beds, 51.5609690133776, -0.03910475366907278)
This is the largest engraved slate stone (16.52cm l/ 12.78 w/0.8 h) and it was uncovered a few meters away from s2.fB. Similarly to s1.kC and m.cW its origin has been traced to the Snowdonia region, however its shape suggests that it has been sculpted into a square and this may only be part of a larger engraving. The precision and clarity of the marks is a clue into the high technological skills required to engrave this stone. It depicts a circular blessing, which might have been performed by voice or several voices. This is suggested by the lingua ignota markings at the centre of the circle. The lines on the inner circle might represent accents and rhythmic patterns.
The image below proposes a digital recostruction of the engravings and was created using high resolution scanning technology.