1. Create a new 500x500 pixel document with a resolution of 100 and name it Crystal. Now press D and fill the document (with Black). Now create a new layer, name it 'circle', then select the elliptical marquee tool and holt down shift to create a perfect circle selection (my circle is about 108px by 108px). Then pick a medium grey color (50%-65% gray) then fill the selection. Then Align the circle to the centre.
2. Now with the 'circle' layer selected merge the layers, then apply an extrude with settings [Type: Pyramids, Size: 14-16px, Depth: 255 Random]. Then apply extrude twice more with settings [Type: Pyramids, Size: 20-22, Depth: 255 Random].
3. Now create a new layer, select a color of your choice and then fill the whole layer with it. Then change the blending mode to 'Color'. Merge with previous layer and there you have it, some color added.
There you have it. a Nice cool crystal effect which can be added to background of all sorts. I actually added one to the final product of the glow waves.
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