This is a stunning piece of vintage glass.
The takes the form of an anamorphic bowl with a wavering edge at the top.
It was designed as a decorative bowl and was never intended for use as an ashtray or similar - it is a fine sculptural piece. It has four lobes which have been hand-blown and than all twisted over.
It is a large piece with a good weight to it - and is a bit of a showstopper on display.
The centre of the dish has a black trail of glass contained within the top clear layer - and this resembles a spider's web. The lines radiate outwards in an attractive geometric pattern, as photographed.
The main body colour is ice white with pale blue shades to the edges.
Flip the bowl over and you can see the clear layer on the back covered and embellished with oodles of specks of silver aventurine flecks that you might find in gold in Cordonato Oro pieces.
This must have taken great skill to have made this lovely piece - I am surprised that it has not been signed - it probably in its past had a paper label with details of the makers - but this is no longer present.
Looking at similar pieces of Venetian Murano glass dating to the 1940s / 1950s - I am suggesting a probable attribution to Barovier and Toso.
Dimensions: 8 inches in diameter and with a height of 3 1/2 inches.
It has a good bit of weight to it and unpacked it is 2.4 kg.
Sadly, it is for UK posting only. I will have to send it to you with Parcelforce48 - this will be tracked, signed for, and insured in transit. This will cost about £10