File:IPLab3ForeignBodyGranuloma5.jpg|This is a fully-polarized view of lung showing numerous birefringent particles.

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== Study Questions ==

* <spoiler text="Compare and contrast the tissue reactions to carbon (anthracosis), talc, and silica. What factors are important in the pathogenesis of tissue injury due to these foreign materials?">Carbon is relatively inert and leads to little if any tissue damage.