The underwater location of “Południowa Ławica Środkowa – Bałtyk Południowy” deposit in the Baltic Sea minimises weathering and disintegration processes of the rock material. The aggregate remains under constant pressure and temperature and in ambient conditions of negligible variation. The material is predominantly magmatic and metamorphic rock, mainly granite and gneiss of the highest processing value and practically devoid of lightweight or alkali-reactive rock types, which may pose a hazard in regards to concrete.
The test results for LA, micro-Deval and PSV explicitly demonstrate high resistance of the aggregate to abrasion and disintegration which is equal to or often higher than that of the commonly used rock materials sourced from the mines in southern Poland and critical to the production of high-strength concrete.
Equally important are other durability parameters determined in frost resistance and water absorption tests, the results of which award our material the highest quality grade. The process of mining aggregate from the sea bottom and its secondary washing at the processing plant ensures steady and extremely low dust content, which greatly facilitates working with the material, particularly in the production of concrete.
All parameters of the aggregate material are routinely tested at an accredited laboratory under a certified Factory Production Control System 2+, which enables their continuous monitoring and uniformity.