How Deep

A very complicated answer. Depends on how long ago the coin was deposited in any particular location and that location's soil conditions. Sedimentation rate from normal soil build-up and wear-down (accretion and avulsion) can vary from an inch a century to more than two feet in the same period of time depending on rainfall amounts, dust layering, wind erosion and deposition, organic (plant) detritus deposition, and local human activities. I've been on archeological digs where mid-19th century coins were unearthed 18" to 24" down in a moderate climate. If someone had been around to drop a coin, say 1000 years ago at the same site, it might be down six to eight feet. Alternatively, with high soil erosion, I've found coins and bullets laying on the surface where they were exposed after more than a century of burial.

I would state that the depth to which one must dig to find a coin would be the limit of the metal detecting device used. I don't know how deep a very expensive and sensitive machine can detect a coin, but I doubt it's as deep as six feet. Some things are not meant to be found.

Fred

The average is probably somewhere around 6 to 8 inches in average conditions ,, but with todays detectors 12 to 14 inches is not out of the ordinary.

Metalman