https://www.thoughtco.com/plutonic-rocks-1440845
Jan 10, 2019 · Plutonic rocks are igneous rocks that solidified from a melt at great depth. Magma rises, bringing minerals and precious metals such as gold, silver, molybdenum, and lead with it, forcing its way into older rocks.It cools slowly (tens of thousands of years or longer), underneath Earth's crust, which allows the individual crystals to grow large by coalescing, like with like; …