Black Basalt Cobbles 100 x 100 x 50 From £42.59/m2Black basalt setts are a hard wearing natural stone paving option with a dark, understated appearance and excellent practical strength. As a volcanic stone, basalt has a dense internal structure, good resistance to surface wear and strong suitability for outdoor areas where paving needs to cope with regular use, changing weather and long term pressure. One of the key advantages of basalt is its tight composition. While all natural stone has some level