Glassware produced by the A.V.E.M. firm on design by Giorgio Ferro in the early 50s.
It's a technique based on making a hole in the walls of a vase while still hot, and pressing it repeatedly onto a metal plate, so that it becomes very narrow.
A metal tool is then used to start making the hole: this may require several attempts in relation to the thickness of the glass. Once the hole is made, the item is heated as appropriate and the hole is widened at will by twisting the metal tool inside the glass that is thus modeled to obtain the desired shape.This operation, simple itself, requires a good command of the technique.
The first example of vases obtained this way go back to the early 30's, as seen in some pieces designed by the painter Dino Martens for Salviati & Co. The highest level of expression has been actually attained in A.V.E.M.'s "anse volanti", that represent one of the most significant examples of the 50s' style.