Metal detectors are capable of finding gold. Gold possesses distinct properties that allow these devices to identify its presence underground.
How Metal Detectors Find Gold
Metal detectors operate on the principle of electromagnetic induction. A transmitting coil within the detector sends out an electrical current, which creates a primary magnetic field. When this magnetic field encounters a metallic object like gold, it induces small electrical currents, known as eddy currents, within the metal itself. These eddy currents then generate their own secondary magnetic field, which the detector’s receiving coil picks up. Gold is a non-ferrous metal, but its high electrical conductivity allows it to efficiently produce these eddy currents.
Factors Influencing Gold Detection
Several elements impact how effectively a metal detector can find gold. The size and shape of the gold target play a significant role, as smaller gold flakes or nuggets can be more challenging to detect than larger pieces. Gold’s purity affects its conductivity and the strength of the signal it produces, with higher purity gold providing a clearer signal.
The depth at which gold is buried directly influences detectability, with shallower targets being easier to locate. Ground mineralization, caused by conductive minerals like iron oxides in the soil, can interfere with a detector’s signal, creating “noise” that can mask the presence of gold. Some detectors can adjust for this interference through ground balancing.
Detector technology also plays a role, with Very Low Frequency (VLF) and Pulse Induction (PI) detectors being common types. VLF detectors are known for their sensitivity to smaller gold nuggets and their ability to differentiate between metals. In contrast, PI detectors are generally less affected by highly mineralized soil and can often detect gold at greater depths, particularly larger pieces.
Interpreting Gold Signals
Metal detectors provide various forms of feedback to indicate a target, including audio tones and visual display numbers. Gold typically produces a distinct audio tone that can be learned and recognized by experienced users. Many modern detectors also feature a visual display that shows a Target ID number. This number helps classify the detected metal, with gold usually registering within a specific range of numbers, distinct from iron or other common trash metals.
The process of “discrimination” allows users to filter out unwanted metals based on their conductivity properties. However, setting discrimination too high can cause the detector to ignore small gold pieces, as their signals might resemble those of unwanted metals. Distinguishing gold from other conductive metals requires practice and familiarity with the specific detector’s responses.