A textile fibre with therapeutic advantages for the wearer and which emerges, phoenix like, from the ashes produced by incinerating a marine plant is one of the latest technological developments from the l50-year-old house of Zegna Baruffa Lane Borgosesia. The yarn spun from this unusual raw material, which will be marketed as Thalassa, is sourced from algae, the microscopic organisms responsible for turning the surface of garden ponds green during the summer months.