Blue - online puzzles

Blue

Blue is one of the three primary colours in the RYB colour model (traditional colour theory), as well as in the RGB (additive) colour model. It lies between violet and cyan on the spectrum of visible light. The eye perceives blue when observing light with a dominant wavelength between approximately 450 and 495 nanometres. Most blues contain a slight mixture of other colours; azure contains some green, while ultramarine contains some violet. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering. An optical effect called the Tyndall effect explains blue eyes. Distant objects appear more blue because of another optical effect called aerial perspective.

Blue has been an important colour in art and decoration since ancient times. The semi-precious stone lapis lazuli was used in ancient Egypt for jewellery and ornament and later, in the Renaissance, to make the pigment ultramarine, the most expensive of all pigments. In the eighth century Chinese artists used cobalt blue to colour fine blue and white porcelain. In the Middle Ages, European artists used it in the windows of cathedrals. Europeans wore clothing coloured with the vegetable dye woad until it was replaced by the finer indigo from America. In the 19th century, synthetic blue dyes and pigments gradually replaced organic dyes and mineral pigments. Dark blue became a common colour for military uniforms and later, in the late 20th century, for business suits. Because blue has commonly been associated with harmony, it was chosen as the colour of the flags of the United Nations and the European Union.In the United States and Europe, blue is the colour that both men and women are most likely to choose as their favourite, with at least one recent survey showing the same across several other countries, including China, Malaysia, and Indonesia. Past surveys in the US and Europe have found that blue is the colour most commonly associated with harmony, confidence, masculinity, knowledge, intelligence, calm, distance, infinity, the imagination, cold, and sadness.

Pueblo on the hillside (Spain) online puzzleYarns online puzzlePort in Tromsø (Norway) online puzzleThe ferris wheel online puzzleButtons ... puzzle online from photoValley in the Triglav National Park (Slovenia) puzzle online from photoFlorida Keys’ Island Beach (USA) online puzzleWaves smashing against rocks in Tortoli (Sardinia) puzzle online from photoCoast near Bayahibe (Dominican Republic) online puzzleKarácsonyi Puzzle puzzle online from photoPanorama of Dresden (Germany) puzzle online from photoTallinn online puzzleWooden houses on stilts in Bocas del Toro (Panama) puzzle online from photoYorkshire Terrier Puppies puzzle online from photoChurch of Transfiguration on the island of Kizhi (Russia) online puzzleFishing village on the island of Paros (Greece) puzzle online from photoBeach in the city of Sousse (Tunisia) online puzzlePanorama of the town of Naxos in the Cyclades (Greece) online puzzleGeyser eruption in the Yellowstone Park (USA) puzzle online from photoCoffee beans puzzle online from photoOwachomo Natural Bridge (USA) online puzzleBodiam Castle in England online puzzleEngine online puzzleThe composition of colorful Easter eggs online puzzle
Maza Bridge in San Vincente de la Barquera (Spain) puzzle online from photoClocks online puzzleReichstag building in Berlin (Germany) online puzzlecupcake online puzzleSunset on the pier in Sopot (Poland) puzzle online from photoArchitecture of Santorini (Greece) online puzzleYellow lily puzzle online from photoTenement houses in the old town of Riga (Latvia) online puzzleColourful clips online puzzlemandala 2 online puzzleSkoda Roomster puzzle online from photoPraia da Marinha (Portugal) puzzle online from photoPort town of Pučišća on the island of Brač (Croatia) online puzzleSiberian Husky puppies online puzzleSunflowers online puzzleMap, compass and magnifying glass puzzle online from photoAn old bicycle as a flowerbed online puzzleThumbtacks puzzle online from photoSugarloaf Mountain (Brazil) online puzzleView of fishing village of Reine (Norway) online puzzlepics online puzzleLiving room with a fireplace at Christmas puzzle online from photoImages puzzle online from photoBeach at La Manga Peninsula (Spain) online puzzle