Montague Pied A Terre has been equipped with a weather vane. The task of installing it was other than easy but it was a worthwhile endeavor. The angel is almost three feet in length, is three dimensional (not two dimensional and flat) and it's made of copper. The copper was most beautiful when it was initially ensconsed over the porch but the weather and elements have quickly turned it from a bright and shiny surface to something more subdued. As time goes on it will most likely turn its surface to a green patina.
The green patina that forms naturally on copper and bronze, sometimes called verdigris, usually consists of a mixture of chlorides, sulphides and carbonates. copper carbonate or copper chloride. Atacamite is another name for the patina compounds. Verdigris is usually more specifically the artificial form and can be produced on copper by the addition of vinegar (acetic acid). Such a verdigris is water-soluble and will not last on the outside of a building like a "true" patina. It is instead usually used as pigment.
One example of a patina is a green surface texture created by slow chemical alteration of copper, producing a basic carbonate. It can form on pure copper objects as well as alloys which contain copper, such as bronze or brass.
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