Mosaics have been observed since first noted by Cromwell Mortimer in 1730. They were generally of red tesserae, but the main pavement is more complex consisting of white, yellow and red tesserae forming flowers, knots and guilloches. In 1896 Laver observed a wall some 2ft high and 3ft wide, and in 1953 Hull heard that a circular foundation (apse?) had been found. Tesserae have been found as far as Yew Tree House, where a midden was also found. Finds have been reported, but none has survived except fragments of Samian and the rim of a mortarium which was found in 1921 under the pavement in the church. The area covered is extremely large.<1> Other refs: <2>-<12>

In 1965, workmen of the Eastern Electricity Board opened up a hole (c.3ft. square x 6ft. deep in size) in the footpath near the front gate of Yew Tree House (16 Coast Road). In the NE corner, at a depth of c.4ft. (c.1.2m), there was evidence of a floor or pavement c.4in. thick surfaced with red tesserae. The short account of this find reports that, from ifs depth and position, it would appear to be a continuation of the pavement, seen in the garden of Yew Tree House in 1961, to the east, immediately inside the front gate.<16>

In 1990, a test pit was dug to 1.2m by the south wall of the present church hall. Natural was not seen. Below the 150mm of topsoil was loose silty clay to a depth of pit. Finds from this include one piece of medieval peg tile and two plain red tesserae with mortar adhering to underside. Another tessera was seen in an adjacent flower bed. None of the finds were kept. The recorder suggests that this test pit was dug through the construction trench for the church hall and, therefore, the finds are redeposited.<13>

In 1991 two trial holes (A and B) were excavated in preparation for the proposed West Mersea church extension. A third hole, C, was dug but abandoned after modern pipes were uncovered:

Hole A : (1.5 x 1m) was sited on the line of the proposed foundations for the eastern extension. Below the topsoil to a depth of 1.12m was a homogenous sandy loam. Finds were found in both layers, these were all disturbed and appeared to have no context. Human bone was found but it was similarly disturbed; the bone was residual and did not represent an 'in situ' inhumation. Two coffin fittings (handles) and a nail also seem to be associated with residual deposition of graves. Other finds included peg and flue tile, and two sherds of pot, one sherd possibly being Roman.
Hole B: (1 x 1m) was sited on the line of the proposed foundations for the western extension. Below the topsoil was a sandy loam to an arbitrary depth of 76cm. No features were found but residual finds were made suggesting that the material had been redeposited. Finds of human bone, slate, tile (of varying age) and sherds. The sherds ranged from samian ware to medieval and post medieval.<14><15>

A test pit (Test Pit 1) excavated by Access Cambridge Archaeology in 2006 in the garden of Yew Tree House, High Street, produced three sherds (7g) of Roman pottery, a fragment of Roman box-flue tile and two small tesserae. The test pit also produced a small number of sherds dating to the medieval and post medieval periods.<17>

The area of these finds, and hence the mapping of the site (or sites) is ill-defined.