With a smile on her tanned face, skiier Kazumi Furukawa can vividly recall the time three years ago she stood here on Mount Zao and looked down at fir trees turned into glittering crystals. "The sky was cobalt blue and I could see the tiny snow crystals on the tips of the tree branches," Furukawa, 56, remembers. But these days the natural phenomenon is growing rarer and scientists say the culprit is beyond Japan's control -- industrial pollution from China.