Feathered or Phoenician Glass
This technique was already in use in pre-Roman Phoenician and Egyptian glass. It was later introduced in the Murano glass factories at the end of the 16th century or more probably in the 17th century, and broadly used in the following centuries.
It is obtained by applying vitreous threads while they are still hot around a blown object of another colour. The threads are then combed upwards using a metal utensil with a number of teeth called a sgraffon or manereta (a “comb”) and the resulting effect is a sequence of waves, feathers or repeated festoons. The object thus decorated is further heated, marbled on the metal slab and blown again. Towards the mid-1950s, Fulvio Bianconi

Fulvio Bianconi, Parrot and Cock in polychrome glass, 1953 ca