Explanatory notes
… particles naturally agglomerated by calcareous or siliceous materials. Basalt is also an igneous rock, blackish, very … hard igneous rocks (e.g., syenite, gneiss, trachyte, lava, diabase, diorite, phonolite), as well as calcareous … heading. Ecaussine, sometimes known as “ petit granit ”, “Belgian granite” or “Flanders granite”, falls in heading …