Blick Art Materials
07-20-2011, 01:03 PM
Blue Wool Scale
The Blue Wool Scale was originally developed to determine the lightfastness, or permanency, of a fabric. In other words, to see how permanent colors in a fabric were from fading. How it worked was that two pieces of blue wool were used. One piece of wool was placed in a dark location, which was considered the original coloring of the fabric. The other piece of wool was placed in direct sunlight for 3 months. After the 3 month span, both pieces were compared to rate the degree of fading. A rating of 0-8 was established, 8 being the highest lightfast rating, 0 being the poorest.
This rating system has been adapted into the art world to measure the permanence of pigments, most commonly in specialty pencils but with all media with pigment, such as pastel and paint. While the method itself is not employed, the rating system of 0-8 is still implemented with a rating of 6 or higher being deemed lightfast.
FAQ:
Is there a brand that solely uses the Blue Wool Scale?
Yes. Derwent lightfast ratings are tested using the Blue Wool Scale.
http://www.dickblick.com/brands/derwent/
-Kristal F.
Product Information Specialist
For further assistance using art supplies, feel welcome to contact our Product Information Department at
1-800-933-2542 or e-mail us at info@dickblick.com (info@dickblick.com). Hours of operation: M-F, 8:00am-5:30pm CST.
The Blue Wool Scale was originally developed to determine the lightfastness, or permanency, of a fabric. In other words, to see how permanent colors in a fabric were from fading. How it worked was that two pieces of blue wool were used. One piece of wool was placed in a dark location, which was considered the original coloring of the fabric. The other piece of wool was placed in direct sunlight for 3 months. After the 3 month span, both pieces were compared to rate the degree of fading. A rating of 0-8 was established, 8 being the highest lightfast rating, 0 being the poorest.
This rating system has been adapted into the art world to measure the permanence of pigments, most commonly in specialty pencils but with all media with pigment, such as pastel and paint. While the method itself is not employed, the rating system of 0-8 is still implemented with a rating of 6 or higher being deemed lightfast.
FAQ:
Is there a brand that solely uses the Blue Wool Scale?
Yes. Derwent lightfast ratings are tested using the Blue Wool Scale.
http://www.dickblick.com/brands/derwent/
-Kristal F.
Product Information Specialist
For further assistance using art supplies, feel welcome to contact our Product Information Department at
1-800-933-2542 or e-mail us at info@dickblick.com (info@dickblick.com). Hours of operation: M-F, 8:00am-5:30pm CST.