Phathological findings. A. On medium power, a section shows many chronic inflammatory cells with rare alveolar architecture. In the middle and upper parts of this figure, foreign body granulomas are observed (H&E, 200X). B. On high power, the granuloma shows several tiny, conspicuous, spiculated, and scattered metallic substances, which can be discriminated from usual calcified spherules (H&E, 400X). C. In the polarizing microscope, a vivid, intense birefringent metallic structure is noted in the metallic substances(400X). D. On medium power, the section shows dense fibrosis and rarely viable lung parenchyma (H&E, 200X).