The two main devices (symbols) in the Leister blazon are the fleur-de-lis and fess. The two main tinctures (colors) are azure and or.
The bright, strong blue color in Heraldry is known in English as azure, and similarly in other European languages – azul in Spanish, azurro in Italian and azur in French. The word has its roots in the Arabic word lazura, also the source of the name of the precious stone lapis lazuli 1A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1894, Entry:Azure. Despite this, those heralds who liked to associate colours with jewels chose instead to describe blue as Sapphire. According to Wade, the use of this colour symbolises “Loyalty and Truth” 2The Symbolisms of Heraldry, W. Cecil Wade, George Redway, London, 1898 P36.
The bright yellow colour frequently found in coats of arms is known to heralds as Or, or sometimes simply as Gold.3Boutell’s Heraldry, J.P. Brooke-Little, Warne, (revised Edition) London 1970, P 27. Along with, argent, or silver it forms the two “metals” of heraldry – one of the guidelines of heraldic design is that silver objects should not be placed upon gold fields and vice versa 4A Complete Guide to Heraldry, A.C. Fox-Davies, Bonanza (re-print of 1909 Edition), New York, 1978, P85. The yellow colour is often associated with the Sun, and the zodiacal sign of Leo.5Understanding Signs & Symbols – Heraldry, S. Oliver & G. Croton, Quantum, London, 2013, P53.
The fleur-de-lys (“flower of the lily”) has a long and noble history and was a symbol associated with the royalty of France even before heraldry became widespread. 6Boutell’s Heraldry, J.P. Brooke-Little, Warne, (revised Edition) London 1970, P 3. The Lily flower is said to represent “Purity, or whiteness of soul”7The Symbolisms of Heraldry, W. Cecil Wade, George Redway, London, 1898 P134 and sometimes associated with the Virgin Mary. The fleur-de-lys is also used as a small “badge”, known as a mark of cadency to show that the holder is the sixth son of the present holder of the arms 8A Complete Guide to Heraldry, A.C. Fox-Davies, Bonanza (re-print of 1909 Edition), New York, 1978, P489
The fesse (also found as fess) is one of the major ordinaries to found in heraldry, being a bold, broad, horizontal band across the centre of the shield. It may originally have arisen from the planks of which a wooden shield can be constructed, the centremost plank being painted a different colour 9A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1894, Entry:Fesse. It is instantly recognisable as a symbol, for example the arms of COLEVILLE granted during the reign of Hery III are simply or, a fesse gules. With this clear association with the construction of the shield itself, Wade believes that the fesse can be taken to be associated with the military, as a “girdle of honour”.