Rock-solid career path
At noon, a group of students walked the mountain road at Doi Kham, Chiang Mai, under the Sun’s heat. With sweat rolling down their faces, each of them stalked the area with a rock hammer. After a while, they crouched down and broke apart a small chunk of rock with their tools. One of them poured out a droplet of acid. Suddenly, a fizz started to form on the rock.