Bleu celeste

Bleu celeste (/ˌbluː səˈlɛst/, "sky blue") is a rarely occurring and non-standard tincture in heraldry (not being one of the seven main colours or metals or the three staynard colours). This tincture is sometimes also called ciel or simply celeste. It is depicted in a lighter shade than the range of shades of the more traditional tincture azure, which is the standard blue used in heraldry.

Generally considered to be European rather than English or Scottish, after the First World War it started to appear in England in arms and badges relating to the Royal Air Force, though it is still doubtful if any more than a dozen examples could be found in British heraldry, and most British heralds consider it unheraldic. While in the post-World War I period bleu-celeste is depicted as a darker shade, in prior times it was depicted as very light, and has even been treated as a metal, as azure charges have been placed on a bleu celeste field, and vice versa.

Regardless, bleu celeste is still used by heraldic authorities, such as Britain's College of Arms in London, with one example of the arms of Jacob Flamberg being granted in 2016 using bleu celeste in the blazon for the field, mantling and charge, in each case per pale/party with sable.

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