Pneumoconiosis is lung disease secondarily to the exposure to inorganic dusts, in many  developed countries related to now decaying industries such as coal mining.

The prolonged expsoure to these dusts can give rise to lung fibrosis, which on occasion may progress to a conglomerate form mimicking masses in the lungs (PMF).

Nodularity often accompanies the fibrosis.  Many types of coal have silica components, which results in the more specific term of silicosis.

Calcified mediastinal lymph nodes may also be a feature.