every metal has a different "phase response" BUT its not a "resonance" or "A"
"frequency" & most CONSUMER metal detectors only measure target conductivity
& gold has a similar phase responses to tinf…
every metal has a different "phase response" BUT its not a "resonance" or "A"
"frequency" & most CONSUMER metal detectors only measure target conductivity
& gold has a similar phase responses to tinfoil
1925 Gerhard Fischer developed a portable metal detector & later electro-magnetical tunable induction device coils were used from 3 to 100 kHz & by the 1960s, the first mineral prospecting industrial metal detectors were produced, & widely used as
elements & "metals" from highest to lowest conduction = Silver, aluminum, gold,
copper, low zinc Brass, zinc, hi zinc brass , nickel, tin, iron, lead, platinum, tungsten
Longer waves (low frequency) select for high conductivity targets & penetrate ground deeper
shorter waves (higher frequency) select for low conductivity targets like iron at shallow depth
10 kHz metal detectors find silver coins better than one operating at 20 kHz.
20 kHz metal detectors find small gold particles better than one operating below 10 kHz.
40 kHz metal detectors find even smaller gold pieces better ?
depending on the sophistication , Lead has almost the same signature as gold when metal
detecting as both may set off the same high frequency tone & or register "high" on its scale
pure lead vs hardened shot vs scrap lead fishing weights, may show up in the low range
of conductivity, in roughly in the same range as pure gold or electroplate or coin gold
Gold = 1.754MHz relative to 100MHz NMR frequency of hydrogen
kodu.ut.ee/~laurit/AK2/NMR_tables_Bruker2012.pdf
thoughtco.com/table-of-electrical-resistivity-conductivity-608499
metaldetectingforum.com/index.php?threads/conductivity-and-metal-detecting-explained.283119
https://en.wikipedia.org/wiki/Gold
https://en.wikipedia.org/wiki/Lead
https://en.wikipedia.org/wiki/Tin_foil
https://en.wikipedia.org/wiki/Metal_detector
https://en.wikipedia.org/wiki/Nuclear_magnetic_resonance
citations & archives munged due to youtube link bot & censor flag threats
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