end of a MINE

does any body actualy reached the bordes of a mine ? i mean not level down , but borders . i thought about this and i think that mines cant be infinite (north south etc) so this is my question
+ about silver . from my experience i mostly found silver near entrance (same on the 2nd level), i mean the mine map that was loaded when i entered a mine first . i searched i think in 200-300 tile radius but didnt find any silver away from this first loaded terrain near entrance
+ about silver . from my experience i mostly found silver near entrance (same on the 2nd level), i mean the mine map that was loaded when i entered a mine first . i searched i think in 200-300 tile radius but didnt find any silver away from this first loaded terrain near entrance