Many beginner diggers have a lot of questions about metal detectors. And often the answers to them have to be searched bit by bit on different resources. We have selected the 10 most common questions about searching with a metal detector and will try to give detailed answers to them.

The list of frequently asked questions on metal detectors is given in a convenient Q&A format. So let's start simple:

1. Which metal detector is suitable for a beginner?

The path of the treasure hunter should be started with inexpensive entry-level models. The main thing is that they have the basic functions necessary for a comfortable search. The best choice for beginners will be metal detectors with a display and metal discriminator, which separates the types of materials and filters out all kinds of iron rubbish. The digger will have to master the basics of searching for valuables, learn to recognize finds by sound.

To learn the basics, it is best to get an entry-level metal detector with a metal discriminator and an info display.

An expensive and advanced metal detector is a dubious option for a novice treasure hunter. With the abundance of functions and settings, an inexperienced user will definitely get confused. It is necessary to “grow up” to advanced class models. Switching to them is recommended when the capabilities of an entry-level device no longer meet the needs of a treasure hunter.

In general, professional metal detectors differ from basic level devices according to the following key criteria:

  • quality of discrimination;
  • search depth;
  • anti-interference feature;
  • the number of settings that allow you to finely ground balance the metal detector.
Metal Detectors with LCD Display

2. What does frequency mean in a metal detector? At what frequency does the metal detector operate?

The detection frequency supported by the metal detector usually refers to the capabilities of the main unit – the actual operating frequency is determined by the specifications of the installed coil. The higher the frequency, the smaller objects the metal detector is able to recognize and the smaller the depth of their detection. And vice versa, at low frequencies, the metal detector "sees" deeper, but the sensitivity of the device suffers.

According to detection frequencies, metal detectors are conditionally classified into the following groups:

  • up to 5 kHz – to search for large metal objects, mainly at great depths;
  • from 6 to 10 kHz – a universal option, "catching" medium and fairly small objects like coins at medium depths;
  • from 11 to 15 kHz – to search for small metal objects at shallow depths;
  • from 15 kHz and more – to search for the smallest objects lying near the surface (for example, small gold nuggets, pins and needles).

Most metal detectors are multi-frequency. They support not one value, but a certain range of frequencies, which allows you to customize them for specific search tasks.

Metal Detectors 6 – 10 kHz

3. What is the best frequency for finding gold?

To search for nuggets, small grains of gold and small jewelry, high frequencies are widely used – over 15 kHz. The fact is that low-frequency metal detectors are good at finding objects with excellent conductivity. But gold does not have such properties. According to the metal discrimination scale, gold products have similar parameters with oxidized iron. In this regard, it is worth choosing a metal detector with an extended range of sensitivity to ferrous metals.

High frequencies (from 15 kHz and more) are usually used to search for gold.

The metal detector can also see gold rings, earrings and chains at medium frequencies. For this, devices designed specifically for detecting gold are suitable. Such models usually have a separate "Gold" search mode.

4. At what depth does the metal detector work?

It is difficult to give an exact answer to this question. The detection depth of metal detectors depends on a number of factors – from the operating frequency and size of the coil, to the characteristics of the soil. So, the penetrating ability of the detector is reduced by mineralized soils. In this situation, models with a ground balance function come to the rescue, which can be manual, automatic and combined. By adjusting to the composition of the soil, false signals of the metal detector are minimized and effective recognition of metal objects at a greater depth is ensured.

An important role in the depth of the search is played by the size and shape of the object. The larger the metal object, the deeper it can be "seen" in the soil. The easiest to detect at great depths are flat, ring and loop-shaped objects – it's all about their increased conductivity. But objects in the form of a rod or coins standing on the edge are much more difficult to recognize. Metal detectors "see" them at shallow depths.

Standing coins are much more difficult for a metal detector to detect.

The chemicals in the soil are corrosive to metals, causing them to oxidize. Rust is partially absorbed by the surrounding soils, and the soil becomes more conductive. As a result, some metal objects appear larger than they really are. Rusty objects are easier to detect at medium and large depths of search. This cannot be done with gold and silver, since these metals are almost not amenable to oxidation.

When searching with a metal detector, most artifacts are found at a depth of up to 25-30 cm. There is not much point in chasing larger numbers, unless the detector is supposed to be used for specific tasks in the manner of searching for sewer pipes at great depths. After all, the deeper the signal gets, the greater the likelihood of errors, in addition, you will have to dig deep holes.

5. What metals does the metal detector react to and what metals it does not see?

Conductive and magnetic metals are the easiest to detect: iron, chrome and carbon steel, tungsten carbide, etc. These materials have a significant effect on the magnetic field, so the metal detector gives clear and understandable signals. Non-ferrous metals (copper, aluminium, brass, bronze) also have good conductivity – there are usually no problems with them either.

But what do metal detectors “see” badly? It is difficult to recognize non-magnetic metals with high resistance and low conductivity. For example, stainless steel and various alloys from it. It cannot be said that a metal detector will not detect stainless steel in the ground, but such tasks are not easy for most detectors.

6. What is discrimination in a metal detector?

The discriminator allows you to filter finds by material without digging them out. The discrimination function is being introduced into metal detectors for targeted search – so that the devices do not react to useless trash like bottle caps, pieces of rebar, foil from cigarette packs, etc. This simplifies the search and saves the digger from the extra work of extracting uninteresting objects from the ground.

In models with a metal discriminator, you can set search restrictions by type of metal.

In advanced models of detectors, it is possible to obtain information about objects in the ground from the numerical values of metals that are displayed on the screen. Basic metal detectors do not have such options, however, learning to search using discrimination is not difficult. At zero discrimination, the detector sees all metals within the detectable range. By increasing the discrimination value, metal rubbish starts to be ignored. The best way to practice is to scatter some sample targets at a small distance from each other. Starting from the lowest discrimination point, scan these objects and gradually increase the discrimination threshold until the object is ignored. Remember the results or write them down – this way you can learn to set discrimination literally by sound. The feature saves time and effort, helping to decide whether to dig or not.

Metal Detectors with Discriminator

7. What does the size of a metal detector coil affect?

The depth of the search and the accuracy of target detection depend on the size of the coil. A universal option for amateurs and seasoned diggers are 9-12 inch diameter coils – this is the most popular size that works well in most conditions. Small coils 5-9 inches in diameter are better at "seeing" small objects, but they are not able to look deep into the ground. Large coils with a diameter of 13-20 inches cover large areas of the ground and increase the depth of detection. The reverse side of their medal is an inaccurate indication of the location of small objects, which is why user have to dig a larger hole.

Visual difference between detection zones when using coils of different sizes.

Coils for metal detectors differ not only in size, but also in shape:

  • round – with high accuracy determine the location of the find, but are sensitive to highly mineralized soils; due to the small width of the captured area, the time and effort for search at large areas increase;
  • elliptical – elongated coils provide a somewhat "stretched" electromagnetic field, which expands the size of the captured area, but somewhat reduces the detection accuracy;
  • rectangular – typical for deep metal detectors;
  • butterfly – by design, such coils consist of two ellipses, partially combined and resembling butterfly wings; DoubleD coils are produced in a similar form – the signal in them has the shape of a cylinder, which makes it possible to uniformly scan the area under the coil.

8. What are metal detector false signals and why do they occur?

Phantom signals of a metal detector occur for a reason. Most often, false signals are caused by natural iron oxides in the soil. Soils with their high content are called highly mineralized. For searches in mineralized soil, the ground balance function will come in handy. Some models will automatically ground balance, while others will need to be adjusted manually. Note that when moving from place to place, the mineralization of the soil often changes – sometimes it may be necessary to frequently adjust the metal detector. Also, the number of false signals can be reduced by decreasing the sensitivity of the device.

Interference in the operation of the metal detector is created by nearby power lines and high-voltage mains. The anti-interference function will help to avoid false signals when searching near such places.

Less common causes of phantom signals are wet dew, shoes and clothes with metal elements, jewelry on the fingers of a digger, and other metal detectors nearby. When searching for relics together with hobbyists, it is advisable to disperse at a distance of at least 3-5 meters from each other.

Metal Detectors with Anti-interference

9. Why do experienced diggers use headphones?

Experienced diggers are able to distinguish finds by sound. Good headphones improve the audio signal of target detection and help you decide whether to dig or not. The use of headphones increases the chance of successful finds and significantly reduces the time spent digging for useless garbage.

Headphones allow you not to be distracted by external factors, to “hear” better and understand the nature of the finds.

Another important argument in favor of headphones is that they can significantly reduce the external noise factor (wind, road noise, waves, etc.). As a result, the digger will be less distracted and hear signals more clearly. In addition, headphones reduce the attraction of unwanted attention to your person.

10. Where is it forbidden to search with a metal detector?

When searching for treasures and artifacts with a metal detector, you must comply with current legislature. One of the countries most loyal to diggers is Great Britain. To search for historical finds, you need to obtain a license (issued easily) and join any search community. And since most of the land in the country is private, you will also need permission from the land owner. If valuable finds are discovered, the landowner will share with you, but the priority right to buy artifacts is given to national museums. Beach search in England is allowed for a separate fee.

Until 2018, Poland had very loyal legislation. However, it has been tightened up a lot. From now on, only members of official organizations are allowed to dig, and strict records are kept for each find. The violation of the law will cause a large fine or even imprisonment for up to 2 years.

The laws of Ukraine prohibit amateur searches in places where excavations can damage the "cultural layer", as well as in protected areas, locations of historical battles. In all other places, digging is allowed, and search is also allowed in regularly cultivated fields. To avoid misunderstandings, do not arbitrarily enter private territories. And if the search area is on someone's land, you need to get permission from the owner or manager of the land.

Before you go out into the field, study the legal regulations for prohibitions on searching with a metal detector.

In general, around the world, the use of metal detectors to search for archaeological objects, as well as the conduct of archaeological exploration and excavations, usually falls under the ban. Legislation for each country must be studied separately.


Good luck with your search and have more valuable finds!