Metal detectors have been developed since the start of the 20th century, but they have only been perfected and put into actual use at the start of WW2. Their primary application is scanning the ground for buried objects and individuals mostly utilize them in the process of prospecting, but they are also used by archaeologists and military personnel. They work by transmitting an electromagnetic field into the ground and thus energizing buried objects. Once the objects become energized, they create an electromagnetic field of their own and transmit back this signal to the detector.

Types of Metal Detectors

Three main types of metal detectors exist:

• Very Low Frequency (VLF) detectors
• Multi-Frequency detectors
• Pulse Induction (PI) detectors

VLF detectors are the most popular on the metal detection market. They operate with two coils, one carrying a variable magnetic field, which is used for transmitting the signal and one carrying an antenna for receiving back and amplifying signals coming from objects buried in the ground. VLF detectors operate at a frequency below 30 kHz and currently, they are the most widely used type of detectors.

Multi-Frequency detectors are a technological upgrade to VLF detectors. Since VLF detectors work only with a single frequency, they have a restricted ability, so they cannot scan with multiple frequencies at once. Multi-Frequency detectors solve this flaw by operating with multiple calibrated frequencies at once, which allows you to scan for both small and large buried items at different depths, all at the same time. Given this upgrade, they are, of course, more expensive than VLF detectors. But, you should be careful when buying a Multi-Frequency detector and always double-check with your salesman, since sometimes selectable frequency detectors can wrongly be marketed as Multi-Frequency.

Pulse Induction detectors are quite different from the previously mentioned types. PI detectors are not equipped with two different and separate coils; rather, they use only one coil that is transmitting and receiving the underground signals at the same time. These detectors send short voltage pulses, lasting only milliseconds, to their coils, which then generate a magnetic field that dissipates when the pulse ends. Because of this, the metal objects in the scanned area of the ground become magnetized and by emitting their magnetism, the coil of the PI detector can locate them. PI detectors are the most advanced and most expensive type of metal detector. They can detect objects in various and complex ground conditions and they are excellent for scanning beaches and for discovering gold nuggets.

Choosing the Right Metal Detector

Metal detecting as a hobby is becoming more popular by the day. If you are a gold prospecting or underground scanning enthusiast and you want to buy a metal detector, there are several factors in play before you make your purchase decision. We will try to help you by listing the most important ones that you should consider.

Purpose

Every metal detecting enthusiast has a defined purpose or goal when going out in search of buried items. Today on the market, most metal detectors are made with an all-purpose approach, meaning that they are capable of detecting the majority of items, such as gold, coins, relics and jewellery and it is possible to buy such an all-purpose detector in every price range. These all-around detectors are perfect for beginners and casual prospectors since they are easy to set up and use and have good detecting abilities, but if you are more specific in your treasure hunting, then you might want to look into specialized detectors.

For example, if you are searching for buried artifacts, coins or certain relics, you should look into buying a detector that can scan deeper into the ground, a feature that can come with a higher price. If you maybe want to perform scans around bodies of water like rivers or lakes, you might need waterproof coils mounted on your all-purpose detector, but if you plan on scanning inside the body of water itself, then you will need a special, completely waterproof, detector equipped with technology for scanning salt waters or wet beaches.

On the other hand, if you intend to search for buried gold, then you should look into detectors that have a higher operational frequency and which are equipped with special, smaller coils, that are better are detecting small chunks of gold than regular-sized coils. All-purpose detectors are also good enough for chasing buried gold, but specialized gold-searching equipment can sometimes give you the edge on certain surfaces.

Brand

Just like with any other technology product, the brand plays a big role with metal detectors too. Different brands build metal detectors in different ways, so they will all vary in their power, reliability and quality. As always, the rule of higher price equaling higher quality is applicable. An important thing to consider when choosing the brand is the warranty. Certain brands give you longer or extended warranties, which is proof of their quality. A longer warranty can also come in very handy if something were to happen to your metal detector after the period not usually covered by other brands and can potentially save you a substantial amount of dollars.

Another thing that comes into play when choosing the brand of your metal detector is the accessories that apply to it. Different brands produce different accessories for their detectors, with some having little available options, while others having a wide range of powerful accessories that can significantly improve your prospecting, like for example the GPZ 7000 coil for Minelab detectors.

Budget

This is the first and foremost factor that you should take into consideration before purchasing your metal detector. The prices of detectors come in a wide range, so every person can choose the right one for them, from first-time hobbyists to professional prospectors. Of course, more expensive detectors, like the Minelab GPZ 7000 coil, come with more features and more advanced detecting technology. Being a beginner, maybe it will not be easy for you to quickly learn about all the features and possibilities that a professional or high-end detector offers and professionals might want something more powerful and complicated, which has a higher price tag. Some people treat buying a metal detector as an investment, rather than an expense, because if you strike lucky and find something really valuable, you can turn a huge profit. So, sit down and assess your needs and wants in detail and then set your spending budget accordingly.