Tunnel Mining Chain Saw can extract high grade marble directly without striping maintain skins or soils.Less requirement on land expropriation, less wastes and rubbles, less cost on muck and revegetation, less environment damage.Better block shape and higher yield rate.High extracting efficiency without being affected by weather. Even higher efficiency of future expanding extractions to sides or downward.Low overall cost and low risks. High long-termbenefits.