Explosives company Dyno Nobel has changed its blasting policies to allow workers to call a halt if they fear damaging Indigenous heritage at mining sites. The move follows a similar decision by its main competitor, Australian global company Orica, last week. It comes a year after Rio Tinto blew up 46,000-year-old rock shelters at Juukan Gorge in the Pilbara - a decision that ultimately led to a parliamentary inquiry and the departure of top brass, including the company’s chief…