i think it depends on the shard type, the improvement level (shrine/altar/temple) and possibly also the faction (empire buildings have different models from kingdom buildings).
i just made a screenshot from a game where i turned the camera so it captures a few high level shards (no idea ho i can embed an image, i'll just post a link to the image):
http://dfiles.eu/files/z05q593ni
as you can see on the image (hopefully
) the water temple at the bottom and the air temple within the walls of "raven's heart" don't have the pillar, the life temple on the top right side and the fire temple at the center of the image have that "pillar" effect.
hope that helps