Here you have two videos about the colors

[kml_flashembed movie="http://www.youtube.com/v/7jW1E8f2qO4" width="425" height="350" wmode="transparent" /]

[kml_flashembed movie="http://www.youtube.com/v/kDfm-jkD-0g" width="425" height="350" wmode="transparent" /]