The left hand photo is gold color extracted from mesquite chips with denatured alcohol.  The different yarns were wrapped and the left hand side covered with heavy paper.  The sample set in my southfacing window sill from 9/28/10 - 12/29/10.  There is very little fading between the two sides.  On the right you can see that the color faded slightly but not significantly.

As a comparison, the right hand photo is a comparison of my cactus tuna colors obtained with water fermentation.  You’ll notice that there was significant fading when these yarns were exposed to light.  These yarns were only exposed for one  month compared to almost 3 months for the mesquite on the left.  From top to bottom, we have the mordanted Blanco county tuna, the middle tuna is also on mordanted yarn and the tuna was sourced from Central Market.  The bottom brown color was unmordanted yarn with the Central Market tuna with a vinegar bath.