| When you've painted all the colors you want to test for lightfastness, cut the sheet in half. |
| Bayplast organic pigments, available in several basic colors, offer high color strength and brilliance, superior heat stability, lightfastness and weather resistance. |
| This pigment identification project and a lightfastness standard can only lead to the increased recognition of this fine art medium. |
| Label the swatches carefully, and expose to direct sunlight or a commercial lamp of the type used for testing lightfastness. |
