Silver
Silver is a chemical element with symbol Ag (from the Latin "", derived from the Proto-Indo-European "h₂erǵ": "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining.
Hayes and Harlington Urban District
The green field stood for the district's agricultural background and the amenities of the Green Belt. The silver pall was derived from that in the arms of the See of Canterbury. In 790 King Offa granted lands in Hayes to the Archbishop of Canterbury, and for more than seven centuries the place was closely associated with the See. Among the Archbishops who sometimes resided at Hayes was Anselm, who is commemorated by St. Anselm's Church. The limbs of the pall also suggested runways and together with the wings referred to nearby London Airport. The cog-wheels stood for industry in general and the lightning flashes to the electrical industries in particular.
The circlet of brushwood and deer referred to the name 'Hayes' which is derived from 'Hesa', which was a brushwood enclosure used as a trap for deer. The seax (Saxon sword) came from the arms of Middlesex and the Saxon crown referred to the fact that in that period parts of the district were royal property.