The Brocca To-Be jug, in transparent borosilicate glass, is made of two adjoining tubes — one closed and one open at both ends — of different diameters and heights. The larger-diameter tube is the container, while the smaller one forms the handle, anchored to the main body. Both tubes are cut diagonally relative to their central axis, forming the spout: the design reduces form to a minimum, giving the impression of an assembly achieved with the fewest possible formal interventions.
Borosilicate glass — sometimes referred to by the commercial name Pyrex — is a robust material, known for its resistance to thermal shock and its low coefficient of expansion. It is produced by replacing the alkaline oxides with boron oxide within the vitreous silica lattice, resulting in glass with lower thermal expansion.
It resists chemical agents, making it suitable for laboratory use. It also has excellent transparency and strength, which is why it is widely used in the construction of telescopes, lenses, medical and optical instruments — including components for lighting fixtures — and it also offers high fire resistance, to the point of being used in fire-rated doors.
Thanks to its workability, it is now also widely used for giftware and other applications that make use of the transparency of glass to make an object more functional. Particularly suited to food use, borosilicate glass can in fact be used in freezers, in conventional ovens and in microwave ovens.
