– All products made of concrete, concrete supplies, program for parks and roads are certified by the Mining Institute in Tuzla.

– All mixes and components used for production of concrete, as well as the plants, are certified by the Civil Engineering Institute in Tuzla.

– Regular quality control of limestone fractions from our quarry, as well as concrete products, and testing of samples of ready-mixed transportation concrete is performed by the Slovenian laboratory IGMAT d.o.o. Sarajevo.

– For the production of concrete, as well as all concrete products, only washed limestone aggregate from Boljkovići’s own quarry, Lepenica, which contains 97% calcium carbonate (CaCo3), is used.