The 12 days of Solstice - Day 3 - megalithic art on Newgrange passage stone L19 ... guardian stone?

It's day 3 of my series of photographs called 'The 12 days of Solstice' and today's image features a passage orthostat from Newgrange known as L19 and its beautiful megalithic art. The archaeologist, Michael O'Kelly, numbered the kerb stones, the passage stones and chamber stones. The left-hand passage stones were given an 'L' designation, the right-hand ones an 'R' and the chamber stones 'C'. L19 stands out as the most heavily decorated of the passage orthostats.

Many of these passage uprights have little or no decoration. Some are pick-dressed, a technique which basically removes the outer "skin" of the stone. L19 is heavily pick-dressed above and below the zig-zags and spirals seen in this photo. In fact, some of this pick-dressing has obliterated some spirals on the lower part of the stone. We're not at all sure why this was done.

What we do know is that L19, because of this vividly carved decoration,  is one of the stand-out stones of the narrow corridor leading towards the chamber of Newgrange. The arrangement of the three spirals, with a lozenge in the middle, has led to some people referring to the design as a face, perhaps of some deity or spirit. In this respect, it might be seen as a guardian stone.