at the risk of offending Christine..............
strictly speaking aventurine inclusions means that the sparkle is produced by one of the colours of quartz flakes, since aventurine is a mineral, rather than a metallic source such as copper or gold - so believe Christine is suggesting that the sparkle here is produced by aventurine and not gold - as might be the case with Empoli.
regret I'm not clever enough to see just from these photos exactly what is producing the sparkle here.
Personally, I haven't a clue where this piece of glass was made - sorry to be unhelpful - but I do like it
P.S. as a totally uneducated punt, mho is that the outline shape and rim of this piece are too conventional for Murano - but that is only an opinion.......... can also add that Murano did use copper, silver and gold flake inclusions in their mid C20 wares - and unfortunately, they, or more accurately various authors, used the word aventurine when describing these metallic inclusions - although correctly these descriptions aren't interchangeable. I'm not aware that Murano glass has ever included real aventurine ........... but am sure someone will correct me very quickly if I'm wrong.