Granite, Andesite and Diorite Quarry

These quarrys would generate on the surface in large crater like holes that are full or either granite or diorite. They could have wooden mining structures similar to minesharfts to show that it was abandoned. 

Quarrys give players a dedicated spot to collect these materials in large quantities. This in turn would mean granite, Andesite and diorite spots underground can be made smaller or less common so that they don't make the underground look ugly.