It's not impossible for it to be Murano as well. It looks like it was made in a ballotton mould, which is a often-used Murano technique. Here's the definition from Barovier and Toso's online dictionary of glass terms. The colour is more Empoli, though.
BALLOTTÃ’N
A metal die, giving a cross-relief effect on glass. Inside the die are small square-capped "points" which, when the glass is blown, result in the cross-relief pattern. By covering a PEA stamped in this way with a layer (COPERTA) of glass-using the SOMMERSO technique, for example-an effect is obtained whereby hundreds of minute air bubbles are trapped between two layers of glass.
david