The Extra Objects addon – blender 2.65.

The addon can be found and enable it by using File->User Preferences->Addons.

After you enable this addon.
Just use the keys: Shift/A->Mesh>Extra Objects Menu.
You will see two types of objects.
Diamond

Gem

This is the objects will see in 3D View.

Let’s make a render of this objects.

You can press the key T to bring up the toolbar and you can set all the mesh options.