The ground or field of every coat of arms must be either of metal, colour, or fur. The METALS of heraldry are, Or==gold, and argent==silver, and as the shield of war was antiently of metal, either embossed or enamelled, the retention of the two precious metals as the field of an escocheon is easily accounted for. The COLOURS are gules, azure, vert, purpure, sable, tenne, and sanguine. While some of these terms are French; others, though coming to us through that medium, are originally from other languages. GULES, according to Ducange, is _goulis_, _guelle_, _gula_ sive _guella_, the red colour of the mouth or throat of an animal. Mackenzie derives it from the Hebrew _gulude_, a piece of red cloth, or from the Arabic _gule_, a red rose. _Ghul_ in the Persian signifies rose-coloured, and _Ghulistan_ is 'the country of roses.' It is probably one of those importations from the East which the Crusades introduced, both into the elements of armory and the nomenclature of the science. It was sometimes called _vermeil_[84] (vermilion) and _rouget_. An antient knight is represented as bearing a plain red banner without any charge: "Mais Eurmenions de la Brette La baniere eut _toute rougecte_."[85] The barbarous term _blodius_ was likewise occasionally used to express this colour. AZURE==light-blue, is a French corruption of the Arabic word _lazur_ or _lazuli_. The lapis lazuli is a copper ore, very compact and hard, which is found in detached lumps, of an elegant blue colour, and to it the artist is indebted for his beautiful ultra-marine. This colour, still one of the dearest of pigments, was antiently in great request, and called 'beyond-sea azure.'[86] The lapis lazuli is found in Persia, Bucharia, and China. VERT (French) is light green. This word was applied at an early period "to every thing," says Cowell, "that grows and bears a _green_ leaf within the forest that may cover and hide a deer." Vert and venison, in the vocabulary of woodcraft, were as inseparable as shadow and substance. _To vert_ signified to enter the forest, as in an old song of the thirteenth century: "Sumer is i-cumen in, Lhude sing cuccu; Groweth sed and bloweth med, And springeth the wde nu. =Sing Cuccu, Cuccu!= Awe bleteth after lomb, Lhouth after calvé cu, Bulluc sterteth, Bucke VERTETH, =Murie sing Cuccu=," etc. This colour was antiently called _synople_, and in the Boke of St. Albans _synobylt_, a word which Colombiere derives from the Latin _sinopis_, a dyeing mineral,[87] or from Synople, a town in the Levant, whence a green dye was procured.