Abstract <p>Transition from the specific energy analysis to optimizing process variables in drilling and blasting is discussed as a case-study of the Koktasjal copper–porphyry deposit. The proposed rock hardness determination procedure, as compared with the same-purpose laboratory testing, provides preventive information on rock mass, in real time and without significant expenditures, which is beneficial for practical problem solving, in particular, drilling and blasting optimization and control. Adjustment of a mass blast project in block no. 18-19 at Terekty Mining and Processing Plant is carried out. The powder factor was calculated per each blasthole using the conventional approach and the proposed procedure with regard to the specific energy of drilling. The experimental research with the determination of the drilling specific energy as an optimization criterion of drilling and blasting yielded a positive result and a substantial economic effect. The saving totaled more than 10% of the overall explosive amount put in the mass blast project. The quality of rock fragmentation by blasting was improved as well, which was favorable for the performance of the crushing and sizing facilities.</p>