a close up of amygdaloidal basalt on the coast of northern ireland, uk. white zeolites show in the black basalt

abstract amygdales amygdaloidal and backdrop background basalt black calcite closeup dark geology gray grey grunge igneous ireland magma material mineralogy minerals natural nature northern object pattern people piece quartz rock rocks rough science silica single stone surface texture textured ulster vesicles volcanic wall wallpaper white zeolites