What do Facebook, Twitter, LinkedIn, and Skype all have in common? The color of their logos is blue. Why blue? Research shows that the ubiquitous color has a calming effect that many associate with good qualities such as clean, professional, and trustworthy.
Fasciating articulation of the relationship between desire and melancholy: our inability to be with desire -- our discomfort with things that we want but which remain at a distance to us. (Why the Sky and the Ocean Are Blue: The Color of Distance and Desire | Brain Pickings)
Deep, intense, velvety blue is the best way to describe the color of this sapphire from the Kashmir region on the India/Pakistan border. - Courtesy Edward Boehm, JOEB Enterprises, Chattanooga, Tennessee.
Blue is the color of the sky and sea. It is often associated with depth and stability. It symbolizes trust, loyalty, wisdom, confidence, intelligence, faith, truth, and heaven. Blue is considered beneficial to the mind and body. It slows human metabolism and produces a calming effect. Blue is strongly associated with tranquility and calmness. In heraldry, blue is used to symbolize piety and sincerity.