radiopaque vs. radiolucent

radiopaque vs. radiolucent: What's the difference?

Radiopaque describes materials that are dense enough to resist x-rays shining through them, and so can be seen on an x-ray. Radiolucent materials are those that are not dense enough to keep x-rays from shining through them and so look “clear” on an x-ray. Body tissue is relatively radiolucent, while bone is relatively radiopaque. That’s why you see bones on an x-ray, but not skin and muscle.