Via the info near the hope diamond................it says that diamond form 90 miles deep into the earth........and come to the surface via volcanic eruptions.................but is there a way of going 90 miles under the earth.......................?????????  Or maybe a better question would be..........just how far do the underground tunnels actually go?   From the USA.............through the planets core.............could one get to China???  I bet so............and how long have those bad boys been there..........?????????????????

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Layers of the Earth - page 1 of 5

Have you ever wanted to dig a hole all the way through the center of the Earth to China?  Maybe you have a pen pal over there or something...  Maybe you just wanted to be the first one to do it. Turns out that as soon as you dug a hole about 5 miles deep, you would be burnt to a crisp by all the heat!  No one has even been beyond the first layer of the Earth.  Guess you're going to have to stick to being pen pals...  or buy a plane ticket! By using a variety of advanced techniques, scientists have been able to make a pretty good guess about what lies beneath the surface of our planet.  There are five main layers – the crust, the upper mantle, the mantle, the outer core, and the core.