Thank you 'aba' ; I will add the comments of your reference to the pictures at the Wrld expo to explain.
This must have been something exposed sideways to the competition
These pieces although not flats are magnificient !!
They are of the same déviations to flat as "miniatures" or "bas-reliefs" are, from Retuerto, Cesario, Duthilleul, Meier, .... = unique créations and pièces of art.