Emerald ballroom ceiling

I attended a regional BI (business intelligence) conference at the Regent Esplanade hotel yesterday. All presentations were held in a so-called Emerald ballroom, which is called like that, I'm guessing, because of its oval shape. In addition to glorious marble columns and golden mirror frames, the central ceiling piece is tainted glass:



Btw, sorry for the lower quality, I took this photo with my Nokia...