Middle East: fidelity & truth
Most Religions: divine color
Mexico: mourning, trust, serenity
Blue is a cool color
Blue is a conservative color
Blue is a calm color
During the Middle Ages blue was made from powered lapis lazuli (a rare semi precious gem) which made it very expensive.
The choice of color for the Virgin Mary's robe in most paintings was blue. Although there are spiritual connotations for blue the main reason that Mary's robe is blue is because patrons wanted to honor Mary by using the most expensive color.
The White House and the university websites in using blue as their main color convey trust, confidence, credibility, achievement and stability. I have only included two university sites , GeorgeTown and George Washington from Washington DC but both Howard University and American University also use blue.
Quite a lot of sites for investment and finance companies use blue. They are also making the statement that they are credible, stable and trustworthy.
Blue Cross and Blue Shield Blue in addition to using blue as part of their name, uses it as the main color for their site. As a health insurance organization they will also want to espouse the qualities of confidence and trust along with a sense of good health which are all implied by the color blue.
Nivea also uses blue to show that theirs is an healthy and reliable product.
The spirital symbolizm of blue also works for Notra Dame's Theology Department and when we look at the rest of this univerisity's site we see that they have also used blue as an accent against white for their other department pages The White House visit site