Skilled characters are familiar with the potential hazards posed by the earth when excavating tunnels, expanding caverns, shaping rock and so on. Such hazards include soil prone to liquefaction, weakened bedrock and hidden thermal vents. In addition, characters with this skill will recognise signs of unstable earthworks, solid bedrock and fault lines. They can also identify the likeliest location of precious gemstone deposits, veins of metal ore and lodes of the noble metals. The skill grants a +10 modifier to any Int test involving these tasks.