What is the relevance of Roman mosaics to Contemporary work, is there anything to be gained by studying them?
To answer that we need to look at what it is that makes them so unique in Art History.
Roman mosaicists were all trained to follow what is sometimes refered to as Andamento or what I call ‘The Rules’. There were about 8 rules which applied to the way in which the stones (tesserae) were set, the most obvious of these being the Borderline rule. This is the line of tesserae you see around any figure, animal or human and are the same colour as the background tesserae. This rule can also be seen used in geometric mosaics. The object is, where 2 colours meet, to avoid 2 lines of triangles being set against each other. This creates a sharp line which disrupts the ‘flow’ of the tesserae. By setting a line of background tesserae around the figure then you pull away the triangular tesserae which fill the gaps where you have horizontal lines meeting a diagonal line.
In just one example we see how they were aware of how to avoid certain disruptive effects in the way the tesserae were set.
Now apply this to modern mosaic work, if you wish to create a sharp line then with the knowledge of this rule you know what the visual effect if you break it.