Hi, I have this ashtray, 14cm, easily recognised as Murano. Highly polished base with wear marks. The info I see all say 60's 70's 80's Sommerso. I understand that Sommerso means submerged but could do with an explanation if anyone can offer one. Is there a way of better ageing the pieces rather than having a 30 yr spread ? I did think it had a uranium hint when I saw it because the green has a 'glow' to it. Very clever in my opinion. It is green and a yellowish/amber colour but my eyes are a bit deceiving at times so if there is an official colourway please let me know. Thanks