| 摘要 |
A method and apparatus for using a magnetic element to detect the presence of foreign materials, or anomalies, embedded in an object including placing magnetic field viewing film over an object such as a coin and passing the magnetic element over the object in prescribed patterns. The object to be tested for an anomaly may be covered or encased in magnetic paper. The presence of a foreign material in the object will be detected by the film when a magnetic element passes by the anomaly. An anomaly, such as of tungsten hidden in a gold coin or nugget, is detected by the film due to the disruption of the magnetic field of the anomaly. The film will present a dark spot adjacent to the location of the hidden anomaly. |
