Oldest imagery remaining is 2nd century mosaic icons. One can presume that many of these were taken from then-known images which didn’t survive the iconoclasm heresy, and were attested to by the oldest surviving witnesses of Christ himself.
These images are remarkably consistent with mainstream iconography, but not with the “Western” images.
The beard is short, the hair usually bound back and mid-shoulderblade length, slightly wavy, and dark brown, olive complexioned. A few early icons show short hair, rather than bound back.
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