When you think of things like Gamma or x-rays you cant relate them back to "light" because while there are similarities there are also a number of differences.

When you think of things like Gamma or x-rays you cant relate them back to "light" because while there are similarities there are also a number of differences. Gamma penetrates rocks, these sensors are used to help determine the density of rock by measuring how much was stopped by the material. This is also why Gamma sources are so dangerous, because things like a coat, a car door are effectively "transparent" to them. If there was just "one small stone" in front of the source it would almost be like it wasn't present at all.