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The Blue Breeds: The Chartreux, The Korat & The Russian Blue. In this article we'll explore the differences between three cat breeds that come only in the color blue: the Chartreux, the Korat and the Russian Blue. The first breed is French, the second is Thai, and the third is a breed from Russia. All three are minority breeds — meaning even people who show regularly may seldom see more than one or two of these cats at an occasional show over the course of the show season. This may explain why even experienced exhibitors struggle to identify the breed of a blue cat when spotted on the judging table. Certainly, most spectators at a cat show cannot tell the difference between these three breeds. To make things even more complicated, although the British Shorthair is available in many colors, for years blue Brits were so dominant that the cats were known simply as British Blues. Because British Shorthairs are a popular breed, spectators often think any blue shortcoated cat must be a British Shorthair. For the uninformed, one blue cat looks much like another blue cat – but upon closer examination, the three breeds are quite different from one another. The series of photos and descriptions below analyze and demonstrate those difference.
https://www.showcatsonline.com/tcsco...

The Korat (Thai: โคราช, มาเลศ, สีสวาด, RTGS: Khorat, Malet, Si sawat) is a silvertipped bluegrey, shorthaired breed of domestic cat with a small to medium build and a low percentage of body fat. Its body is semicobby, and unusually heavy for its size. It is an intelligent and playful active cat that forms strong bonds with people. Among the Korat's distinguishing characteristics are its heartshaped head and large green eyes. The Korat is a natural breed, and one of the oldest stable cat breeds. Originating in Phimai, Thailand, it is named after its province of origin, Nakhon Ratchasima Province (typically called "Korat" by the Thai people). In Thailand, the breed is known as Si sawat, meaning "colour of the sawat seed". The Korat is known colloquially as the "good luck cat". Traditionally, they are given in pairs to newlyweds or people who are highly esteemed, for good luck. Until recently, Korats were not sold, but only given as gifts. Korat and Russian Blue both have a grey coat and green eyes. The Korat has a heartshaped face while the Russian Blue has a wedgeshaped face. The Korat is a jungle cat while the Russian Blue is a coldclimate cat. The Korat is a very playful cat while the Russian Blue is a wellbehaved one.
https://en.wikipedia.org/wiki/Korat

The Chartreux is a rare breed of domestic cat from France and is recognised by a number of registries around the world. The Chartreux is large and muscular (called cobby) with relatively short, fineboned limbs, and very fast reflexes. They are known for their blue (silvergrey) waterresistant short hair double coats which are often slightly nappy in texture (often showing "breaks" like a sheepskin) and orange or coppercolored eyes. Chartreux cats are also known for their "smile": due to the structure of their heads and their tapered muzzles, they often appear to be smiling. Chartreux are exceptional hunters and are highly prized by farmers. As for every French cat with a pedigree, the first letter of the official name of a Chartreux cat encodes the year of its birth. All Chartreux born in the same year have official names beginning with the same letter. The code letters rotate through the alphabet each year, omitting the letters K, Q, W, X, Y, and Z. For example, a Chartreux born in 2011 would have an official name starting with the letter G. The Chartreux is always grey. If your cat is a different color, then it is not a Chartreux. The Chartreux is one of only three cat breeds that is always grey. The two others are the Russian Blue and Korat.
https://en.wikipedia.org/wiki/Chartreux

The Russian Blue is a cat breed that comes in colors varying from a light shimmering silver to a darker, slate grey. Their short, dense coat has been the hallmark of the Russian breed for more than a century. The dense coat stands out from the body.
https://en.wikipedia.org/wiki/Russian...