Whether you’re new to metal detecting or a seasoned veteran, you might be asking yourself “How do Metal Detectors Work?”
We all know what a metal detector is used for. The main function of a metal detector is to detect metal! But how does it detect it? How can a metal detector tell the difference between metals?
As a seasoned treasure hunter and detector, these are very common questions I’ve been asked and have answered many times.
How Do Metal Detectors Work?
A metal detector detects the presence of metal. Some detectors can distinguish the different types of metals better than others.
The “Oscillator” or “Coil” is the part of the metal detector that does all the work. An alternating current passes through the Coil and produces a Magnetic Field. Once a metallic object comes close to the coil, another signal bounces back and alerts to the presence of metal.
Every type of metal conducts electricity at different levels. So depending on the level of electric conduit the metal sends back, we can distinguish what type it is.
The display at the top of the metal detector commonly has an indicator that specifies what type of metal was found.
For beginner metal detectors, the display may be digital and easier to read. Older types of detectors have a needle that jumps to a certain level depending on the type of metal.
Some metal detectors produce a different type of beep depending on the type of metal found. Once you become more familiar with using your metal detector, you will be able to tell what type of metal just by the hearing the sound.
Different Types of Metal Detectors
There are many different uses for metal detectors other than finding coins in your backyard. Metal detectors can save lives, help us stay safe and preserve our history.
Here are the most common uses for metal detectors still found today.
Hobby Metal Detectors: Many people have taken metal-detecting as a hobby for different reasons. The basic type of metal detector hobbyists commonly use, have a digital display attached to a Long Rod with a round oscillator at the end of it.
Finding coins and historical artifacts in your backyard can be healthy and provides a lot of fun for all ages.
Security Screening Metal Detectors: 
When someone mentions “metal detector”, the first thing that might come to your mind is the detectors found in airports. These metal detectors evolved from the standard detectors used to find metals in the ground. They’re commonly used to keep us safe in airports, schools, public places and events.
Their settings can be adjusted to increase or lower sensitivity. They give out a high pitched-sound if any metal passes through them to alert the attendant.
Wand Metal Detectors: The “wand metal detector” or “pin-pointer” is also used in-conjunction with the larger versions mentioned above.
They can narrow down and pinpoint the location where the metal is located either on your body or in the ground.
Military Metal Detectors: The Military has been using metal detectors to detect mines since WWII, and continue to use them today. They have a more powerful version of the hobbyist metal detector.
Other versions can be attached to armored vehicles that will also “clear” the mines with chains as they detect them.
Archaeology Metal Detector: 
Metal detectors help archaeologists find ancient treasures buried in the ground. They can specify the depth and location of hidden artifacts to avoid damaging them while digging.
Food-Grade Metal Detectors: Many companies use food-grade metal detectors to ensure the safety of the food they produce. Some foods have natural metals and minerals in their contents. Quality control can monitor the level of metals found in our food to keep us safe.
Recently an Australian company found needles “hidden” in their strawberries. Luckily they used metal detectors to find out before any injuries occurred.