The Shipwreck Effect Defined

Shipwreck Effect Designation

Numismatic Guaranty Corporation (NGC) has adopted a convention for the certification of shipwreck coinage. This is the SHIPWRECK EFFECT designation. Exposure to saltwater has an irreversible effect on the surface condition of immersed coins, and in most cases this prohibits NGC from rendering a precise assessment of a coin’s condition.

Not all shipwreck artifacts are handled similarly. To earn this designation from NGC several conditions must be met. The coins must be recovered in an archeologically sound manner, in accordance with tested and proven procedures, which preserve the history of the wreck.

Furthermore, the coins must be conserved through the least invasive means possible to assure stability of the artifact surface and long-term preservation.


SHIPWRECK EFFECT A - a coin exhibiting minimal surface disturbance from saltwater exposure, and exhibiting superior eye appeal for a shipwreck artifact.

SHIPWRECK EFFECT B – a coin showing evidence of light surface disturbance from emersion in saltwater, and may have some areas of moderate disturbance, not effecting central design elements. Coin possesses above average eye appeal for a shipwreck recovered coin.

SHIPWRECK EFFECT C – a coin displaying moderate disturbance to its surface from exposure to saltwater, while possessing at least average eye appeal for a recovery specimen. Accurate attribution and identification is not hindered by any surface impairment.

SHIPWRECK EFFECT - portions of the coin exhibit heavy to severe disturbance from saltwater exposure, with metal loss affecting the design. While accurate identification and attribution may be possible, it is no longer possible to draw conclusive determinations about the coin’s surface prior to saltwater exposure.


In addition to categorizing the level of surface disturbance, NGC assigns a wear or details grade to coins designated SHIPWRECK EFFECT C or better. This convention attempts to describe the state of wear of the coin prior to shipwreck and saltwater exposure.

UNC (Uncirculated) – a coin showing no wear or evidence of having circulated.

AU (About Uncirculated) – traces of light wear are evident on the high points of the coin’s design.

XF (Extremely Fine) – design features are well defined although light wear is evident throughout.

VF (Very Fine) – major details of the coin are clear although light wear is evident; the high points show moderate wear.

F (Fine) – moderate wear or many elements with heavy wear on high points. The major design elements remain visible.

VG (Very Good) – heavy wear flattens design elements, although major features are clearly outlined.

G (Good) – design details are flat and visible in outline. Some portions of the design may be faint.
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