EWTN Catholic Q&A
colors of Cardinals
Question from Pauline on 04-16-2005:

What is the significance of the two colors the Cardinals wear? I notice some are red and others are almost purple.

Answer by Colin B. Donovan, STL on 04-17-2005:

The cardinals only wear crimson. If you are seeing two colors that is either due to variations in the crimson color used or TV adjustment. Purple is the color of bishops and archbishops.