If you've been wondering what do metal detectors detect, we've got all the answers for you below!
When the topic of metal detecting as a hobby comes up, many often picture a strange old man finding bottle caps on a local beach side. However, in reality, metal detecting can bring lots of joy, possible treasure and even a great form of exercise for us! The thrill of metal detecting is similar to that we get when hunting for Pokémon on Pokémon Go. But instead of virtual creatures, we can hunt for real tangible items!
The more our community begins to spark interest in metal detecting as a hobby, the more we are able to learn about differing kinds of metals and objects, Additionally, we gain a general interest in local history as ancient treasure is discovered.
How Metal Detectors Work
You might be wondering just how metal detectors are able to find and uncover buried goods that might have been in a specific location for so long. The science of it all is actually a lot simpler than you might think!
A metal detector is essentially composed of a battery, a control box, and a search coil. It works by transmitting an electromagnetic field from the coil in the detector to the ground. All metal objects in this field become energized and resend or retransmit an electromagnetic field back to the coil. Once the search coil on the detector receives the transmitted field, it alerts us by producing a specific response signal or sound.
When asking, what do metal detectors detect? Rather obviously, the answer is in the name, metal!
Interestingly though, different kinds of metals transmit distinct electromagnetic fields. Depending on the type of metal detector you have or select, settings can be set to only scan for targeted or desired metals.
This allows users to easily ignore unwanted products, such as bottle caps (depending on our interests, some of us seek these for unique and really vast collections!). We do this by adjusting the setting on the metal detector to not transmit a field that would detect aluminum, a common element in bottle caps.
How Deep Can Metal Detectors Detect
The quick answer, anywhere from 7 inches to 20 feet! There are many factors that effect how deep metal detectors are able to detect. Some of those factors include the soil type, the size of the object, the wetness of the ground, and the type of metal detector purchased.
Mineralized soil tends to give us fake or mixed signals. The size of the object matters as larger metal objects are more easily detected, even though the object may be deeper into the ground. Wet ground tends to uncover newly buried coins especially after a rainstorm.
There are many brands of metal detectors at different price points and different weights. Because of this, the depth of the detecting field is varied.
Kinds of Metals
More commonly, metal detectors are able to and do detect iron, copper, aluminum, tin, nickel, brass, and lead. However, excitingly, these detectors are also able to locate bronze, silver, and especially gold!
We can set our devices to only emit a specific electromagnetic field to find target metals. However, many metals often have similar identifiable features and transmissions. With this in mind, we cannot set the detector to only search for gold, although larger pieces maybe slightly more readable.
Kinds of Objects
General objects that can be found using metal detectors include jewelry and coins. Some have found unique items including a bronze axe head dating back to 1800 BC. Others have found a gigantic chalice made of gold and studded with amber. These kinds of finds are not commonly found and take patience and huge amount of luck. However, such potential treasures make the hunt an ever more enticing encouragement to continue metal detecting!
Enthusiasts have found coins that date back to 155 BC and meteors that have been buried for more than 10,000 years. You can see that the kind of objects that can be found using metal detectors can offer a unique insight into our world’s and people’s history.
Can Metal Detectors Find Gold
The short answer to this question is…yes. Metal detectors can find gold, but with large variance.
While all metal detectors can detect gold, not all are created equally. Several kinds of detectors are made that are more specific and sensitive to gold and are therefore made for those of us solely interested in finding gold jewelry.
Metal detectors designed specifically for gold hunting are made to cancel out mineralization. It is therefore important to understand the geography of the targeted region first.
There are typically two kinds of detectors for gold-hunting. A very low frequency (VLF) detector and a pulse induction (PI). VLF detectors offer a higher sensitivity to small gold nuggets, while PI detectors are able to detect larger nuggets found deeper in the soil.
Pulse Impulse detectors can even function in mineralized soil. They are, of course, pricier as a result and are the newer current technology.
Can Metal Detectors Find Aluminum
Did you know that there have been instances in which the aluminum foil wrapper found commonly in chewing gum set off alert signals at airport security? Strange to think about but this has actually happened before.
Metal detectors are able to find aluminum because as a non-ferrous metal it is naturally non-magnetic. But it is a pretty good conductor of electricity. When it comes to metal detectors, objects made of/or containing aluminum are easily and very commonly detected.
Unfortunately, many aluminum finds are pretty useless. Who wants to find a ring-pull anyway? 🙂
Can Metal Detectors Find Titanium
Titanium is a type of metal that is difficult for us to find as it is not easily detectable by a metal detector. A newer metal detector can be used to find titanium. But Titanium is neither a good conductor of electricity nor magnetic. This means it is super hard to find and requires lots of patience!
First, we have to set our metal detectors to a lower frequency. We also have to be conscious of the type of soil we are searching in. Highly mineralized soil is more difficult to work with unless you have great experience in it.
What is Discrimination in Metal Detecting
After turning on your metal detector and beginning to hunt, you will notice that everything that is detectable will be detected. This includes metallic pieces of trash and mineralized ground too. Discrimination in metal detecting is when we slowly begin to add a differentiator so that only a specific range is detectable.
To learn how to discriminate, you slowly begin by trying to search for coins or foil on the ground and then gradually increase the differentiation. With regular practice, you can begin to determine what type of signals you are picking up and whether you feel its worth the hunt!
Bottom Line
So, what can you find with a metal detector? Lots of things!
From non-valuable mineralized soil, pieces of trash to large gold nuggets. Metal detectors are for those of us who are patient but eager to go on a hunt for treasure!
With time and practice, we can all learn how to search for objects that spark our interests. We also learn about our historical surroundings and often can cash in some of our enticing finds!