Posted 06/07/2010 5:54 pm
Whizzing is a specific method of mechanical cleaning meant to recreate or simulate luster. Surface metal is moved around, usually with a powered rotary wheel or brush, to give the appearance of flow lines that impart luster to a coin. Some whizzing jobs are decidedly amateur and look like a 5 year old took a Dremel to a coin while others are quite skillfully done and can evade detection by most collectors and even dealers. One of the tell-tale signs is an unnatural buildup of metal around devices.
Luster is created by the cold flow process when striking a coin. Think of a planchet as a lump of Play-Doh. Place it between your hands to flatten it, notice how it spreads outward in a radial manner. With metal, the spreading of the planchet is what creates the flow lines that refract the light off the coin surface and create that beautiful shine that we coin collectors affectionately refer to as luster. One thing to remember is that luster can only be created at the time a coin is struck and it has a specific "look", no amount of doctoring can faithfully reproduce the properties of luster.
Luster is created by the cold flow process when striking a coin. Think of a planchet as a lump of Play-Doh. Place it between your hands to flatten it, notice how it spreads outward in a radial manner. With metal, the spreading of the planchet is what creates the flow lines that refract the light off the coin surface and create that beautiful shine that we coin collectors affectionately refer to as luster. One thing to remember is that luster can only be created at the time a coin is struck and it has a specific "look", no amount of doctoring can faithfully reproduce the properties of luster.
