Radioactive dating is also called
Sedimentary rocks are secondary in formation, being the product of precursor rocks (of any type).
The zone of damage is roughly spherical around a central mineral inclusion or radioactive source.
The crystals develop an interlocking texture with some of the trace minerals becoming completely surrounded by later forming crystals.
Volcanic rocks, because they are able to cool and crystalize rapidly, have a very fine-grained texture; the individual mineral grains are too small to see easily with the naked eye.
Metamorphic rocks represent alterations of precursor sedimentary, igneous, or other metamorphic rocks.
Through the cycles of burial, folding, faulting, and subduction of crustal plates, rocks get pushed and dragged down to depths where - under heat and pressure - changes take place.