While these days the association of red and black with so many gambling games could definitely designate them as the "palette of risk-taking," in this classic chicken/egg-type scenario, we have a strong suspicion that there's a less esoteric and more practical reason that those two colors originally came to figure so prominently in the gambling spectrum.
We didn't find any conclusive article that spelled it out for us in black and white (or black and red) and consultation with our eminent duo of gambling historians, Stewart Ethier and David Schwartz (see Expert Contributors) also drew a blank on this one. They did contribute some helpful information and ideas, however, including Stewart's observation that red seems a logical color for the heart suit. Indeed.
Having given the matter some thought, then following up on our instincts with a little googling, we'd put money on the fact that it all has to do with the history of printing. The invention of printing is generally conceded to be one of the defining inventions for the advancement of civilization. Gutenberg's movable-type printing press, invented circa 1440, is often cited as the single greatest invention for world civilization, in fact. Printing itself was invented much earlier -- somewhere between the 4th and 7th century A.D. during China's Tang dynasty, where it began as blocks cut from wood used to print textiles and was then used to reproduce short Buddhist religious texts that were carried as charms by believers. But it was Gutenberg's press that instigated the mass-production of printed materials -- first Bibles, followed shortly thereafter by, among other things, playing cards.
According to Dave Schwartz's esteemed history of gambling, Roll the Bones, the red and black card suits were established around 1480 by agreement of French card makers, and we're guessing that subsequent games like rouge et noir and the color scheme of the roulette wheel all followed from those two colors already being so intimately associated with gambling games. Of course, they also contrast strikingly from the visual point of view, which is useful in practical terms (can't confuse a heart with a spade).
Why did the card makers choose those colors for the suits? We think it was for economic reasons (aren't most things?). Black ink was the first to be developed, with the ancient Egyptians having a version they used for writing on papyrus and the Romans using sepia, the black pigment secreted by cuttlefish. The first "modern" version was "carbon ink" or "India ink," which was used in both the Western and Eastern worlds. It consisted of charcoal or lamp-black, mixed with a gum, glue, or varnish that acted as a binding agent.
In the twelfth century, medieval manuscripts then began to feature metal gall ink, made from mixing crushed soaked "oak apples" (growths on apple trees formed by the egg of the gall wasp) with ferrous sulphate, made by pouring sulphuric acid over scrap iron and mixing the filtrate with alcohol. Ground-up gum arabic was then added to thicken/bind the liquid, which first looks brown but then turns black when exposed to air and light on the page.
Red ink came next and was used extensively in medieval manuscripts for headings, titles, initials, and important dates (hence "red-letter days"). The process for making red ink involved mixing mercuric sulphide with egg white or infusing brazilwood chips with vinegar, and then, in both instances, adding gum arabic.
Green and blue inks existed in medieval times but were much more complicated and costly to produce, and hence are much rarer in early writing and printing. It wasn't until the nineteenth century that classic blue and blue-black inks, which used costly indigo as the color pigment, became widely available, for example. We think this could go a long way toward explaining why card suits, established so soon aft
