Crew colors
Crew colors are colors specifically chosen to represent a crew. Sometimes crew members may be required to paint all ships to be in the crew colors. Furthermore, crew members may be required to have clothing for their pirate in crew colors.
Note that choosing whether or not to have crew colors is up to each crew to decide upon. Preference of crew colors may sometimes be found listed within a crew's info page. There is no in-game mechanism supporting the association. There are times crew colors can be taken off the crew name. Sometimes though the captain will pick pricy colors, and everybody may not be able to afford it.
Example: Sea of Tigers is a crew, but didn't want the crew colors being orange and black because it would be to pricey; so the captain changed them to blue and yellow.