Camera's on the fritz, and am awaiting a replacement - so no images yet I'm afraid.
But the item in question is an incalmo decanter, illustrated in the red catalogue as #4580, with an opaque red bottom half, a transparent smoke-grey upper half and a cased opaque red stopper with an opal-white band. Backstamped with the 3-line mark and with a partial old label.
I was just wondering about its designer - the shape bears strong resemblance to those designed by Bianconi & Venini during the early 1950s - but did Bianconi do incalmo designs for Venini?