Patent ID: 7201324

Claim:
A card and card writer/reader system comprising: an encodeable card having a body having upper and lower surfaces and side and end edges, said body including on at least one of said upper and lower surfaces a data storage section adapted to interact with a data processing station when said card and said data processing station are moved relative to each other to at least one of write encoding signals in said data storage section and read encoded signals from said data storage section, said data storage section including at least one layer of high density storage material for storing data; a diamond-like hardness, abradeable protective coating formed on said at least one high density storage material layer and being selected to have a thickness between a maximum thickness which would materially attenuate encoding and encoded signals passing between said storage material layer and a transducer and a minimum thickness enabling said protective coating to be abraded by usage in an ambient natural atmosphere operating environment for removing therefrom a known quantity of the protective coating; and a writer/reader having a transducer for at least one of writing encoding signals in said data storage section and reading encoded signals from said data storage section during relative movement of said card relative to the data processing station to enable data flow between said data storage section and said transducer.