Diamond is hard, graphite is soft the "lead" of a pencil. Diamond is an excellent electrical insulator, graphite is a good conductor of electricity. Diamond is the ultimate abrasive its most important use , graphite is a very good lubricant. Diamond is transparent, graphite is opaque.
Diamond crystallizes in the isometric system, graphite crystallizes in the hexagonal system. However, at surface temperatures and pressures graphite is the stable form of carbon.
In fact, all diamonds at or near the surface of the Earth are currently undergoing a transformation into graphite, although this reaction is extremely slow. This often occurs deep in the Earth or near magma underground. We often find metamorphic rocks in mountain ranges where high pressures squeezed the rocks together and they piled up to form ranges such as the Himalayas, Alps, and the Rocky Mountains.
Metamorphic rocks are forming deep in the core of these mountain ranges. As the mountain ranges are eroded away over millions of years, the metamorphic rocks are eventually uncovered. The Appalachian Mountains used to be a very large mountain range. Over time the mountains have eroded away and we now can see many different types of metamorphic rocks in the region.
Find Your Rock:. The best places to find diamonds are where burning asteroids collided with Earth a long, long time ago. So why is a ruby red? Depending on the chemical composition, the colour of the rubies vary from deep, dark red to pink. Did you know that sapphires start out with the same mineral as rubies? But they owe their beautiful blue colour to trace amounts of titanium. Just think — sapphires and spaceships have a lot in common! Unlike many other gemstones, emeralds are soft and fragile.
Every geode is a treasure with a hidden gem stone inside! These mineral formations started out as hollow bubbles in a layer of rock. Over time the bubble fills with water, exposing the minerals in the rock to different elements that get trapped inside.
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