1959 Peter Melocco was, by 1959, gravely ill and could no longer be involved in the day-to-day running of the company. His son, John, had joined the company in ‘47 and Galli’s son, Graham, had joined in ‘55. Meanwhile, in the laboratory of (Melocco Brothers’ subsidiary) Certified Concrete, technicians had discovered that, by altering the size and proportions of the aggregate used to make concrete, the strength of the final material could be increased and the cost considerably reduced. It was a discovery of enormous importance for Melocco Brothers and for the building industry.

Certified Concrete had, by this time, become an enormous consumer of sand and gravel — a thousand tons a day of aggregate — which it sourced from Blue Metal Industries. Certified Concrete approached BMI to supply aggregate in the new sizes. BMI refused, so the Meloccos’ team decided to produce the aggregate itself. Peter, Galli and John Melocco had long had their eyes on Shaw’s Island, a large deposit of gravel and sand in the Nepean River.

Some years earlier, they had bought a property adjacent to the island in the hope of eventually gaining access to the gravel. In 1958, the company obtained a permissive occupancy from the NSW Government over Shaw’s Island.

In May ‘59, the Meloccos’ subsidiary, Yarramundi Properties, began extracting two thousand tons a day of gravel and sand — enough to meet the firm’s needs for many years to come. This was viewed as a threat, not only by BMI (which had lost one of its largest contracts), but by other concrete and aggregate producers. A number of public companies — including Ready Mixed Concrete, Standard Cement, Hawksley Pacific, Boral and BMI — approached Melocco Brothers with a view to amalgamation or takeover.