This is a variant of the filigrana already known in Murano in the XVI century. It is obtained by joining two colonical vases under heath, covered externally with thin coloured rods, one arranged clockwise and the other anticlockwise.
A network is thus formed, having a rhomboid-like mesh.
The differences of thickness through the rods, within each quadrangle, cause the typical air bubble. In the early 1900 this technique was adopted by plenty of glass factories to make glass sets.
The most refined and perfect examples are those made at the end of the 20s.
Large dimension blown objects having also geometric shapes and extremely thin sides, in spite of the enormous difficulties of execution, were made by Giacomo Cappellin.