Controlling your light intensity through material parameters

Here are two videos which show how to control the lighting in a scene by adjusting several material channels. The diffuse and ambient amount channels govern how much light is absorbed or reflected back to the viewer. These videos show how to use them.
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Diamonds: Simple brilliant cut

If you enjoyed Gems 101, you may want to learn more about creating 3D gemstones. Here is a brief tutorial on modeling the geometry of a Brilliant Cut diamond, starting from a cylinder, converting into a polygon mesh, and then extruding, scaling, connecting and deleting points.
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