Purpuraires was at the southwest corner of the Roman Empire when the Seven Sages of Greece mosaic was buried in the Mt. Vesuvius eruption of 79 AD.
Some rare snails lived in the water off the tiny islands just off shore. They were the source of purple dyes. The Royal blue dye was a very intense purple-blue color and only the royalty was permitted to use this purple for dying their clothing.
Purpuraires’ location is slightly off the map dated to 54 AD, but it is accurately indicated by the purple circle. There are Roman stone structures from that time still visible near there.
Below is the same picture but with the mosaic removed so the sundial’s white radiant lines and the 31.5° Purpuraires latitude lines may be seen and compared more easily.
Note that at the top circle four white sundial lines go through the top left sage’s eye and two flipped Purpuraires purple lines go through that eye too. Each of these lines was through interesting previously delineated locations on the mosaic. Observe also that the top line through the sage’s eye on our left goes through the top sage’s eye and on through the gargoyle’s eye too.
That line was precisely duplicated at 31.5° and searched across the rest of the mosaic for multiple crossings of places of interest. That 31.5° line was then copied and flipped horizontally and was then searched for hot spots across the picture creating new hotspots. There are ten spots that have three or more independent lines going through them and the spot at the top sage’s eye has six lines. The gargoyle’s eyes are not hot spotted with a circle because it’s difficult to get four independent lines to go through a point near a corner.
All of these picky details point to one thing. There is an intelligence behind the precise locations of these lines. It appears that the lines indicate the most remote sites controlled by the Roman Empire shortly before Mt. Vesuvius erupted.
This analysis points to the borders of the Roman Empire the year Mt. Vesuvius erupted.