I have only a couple of random thoughts to offer: What size is it? It certainly is an odd design for a vase. It looks more like a candle holder, to my eye. As it is, it would be a bit tippy, and that base is so constructed, so smoothed, that it looks almost like it was designed to fit into a base. Not that any of that is really a help, but it's all I have to offer.
Otherwise, and forgive me if I'm telling you what you already know, Murano is a place, not a maker. So unless it is marked Murano, or signed by one of Murano's glassmakers, there's no way to say that it is Murano glass, Sommerso or any other technique.
Murano is a little chain of Islands in the Venetian Lagoon, famous for its many and fine glassmakers. Centuries ago, all Venetian glassmakers were forced to move there because of the fire risk their operations posed to the city.
