moss and lichen textures growing on grey rocks in nature stylish minimalist background

abstract ageing background bark black blackboard blank board brown chalk closeup cracked creative dark decayed design detail dirt dirty distressed dry empty environment expansion floor forest granite green grey grunge hard lava lichen light line log marble material mineral moss natural nature old organic pattern plant protection rind rock rotten rough rugged rust rustic skin slate space stone stump surface texture textured tile timber timbering time tracery tree trunk vein wall wood wooden