FAQ Detectorshop

All the answers about the world of metal detecting

On this page, curated by our Metal Detector Experts and constantly updated, you will find a series of answers to the most frequently asked questions that every detectorist asks themselves sooner or later, especially at the beginning of their journey.

Why is metal detecting illegal?

Using a metal detector in Italy is not inherently illegal; however, it is regulated by specific laws aimed at protecting the country's cultural and archaeological heritage. According to the Code of Cultural Heritage and Landscape (Legislative Decree 42/2004), the use of metal detectors is prohibited near:

• archaeological sites
• landscape-protected areas, such as natural parks and reserves.

This is to prevent unauthorized excavations that could damage historical artifacts. Moreover, the discovery of historical or archaeological items must be reported to the competent authorities within 24 hours; failure to do so may result in criminal penalties. Therefore, the illegality lies not in the use of the metal detector itself, but in its improper use or violation of applicable laws. ​

What is the most powerful metal detector?

The power of a metal detector depends on several factors, including:

• the technology used
• the operating frequency
• the size of the coil
• the soil conditions.

Advanced models like the Minelab Manticore are considered among the most powerful on the market, thanks to Multi-IQ+ technology that enables greater detection depth and more accurate metal discrimination. However, the choice of the "most powerful" metal detector varies depending on the user's specific needs, the type of search (e.g., coins, relics, gold), and the environment in which it will be used. It is important to carefully evaluate the technical features and, if possible, test different models to determine which one is the most suitable for your needs. ​

Where is it forbidden to use a metal detector?

In Italy, the use of metal detectors is prohibited or restricted in several areas to protect the cultural and environmental heritage. Main restrictions include:​

• Archaeological sites: It is strictly forbidden to use metal detectors near recognized archaeological areas, as they may contain historically valuable artifacts.​
• Landscape-protected areas: National parks, nature reserves, and other protected zones are often subject to restrictions to preserve the natural environment.
• Private property: You must obtain permission from the landowner before conducting searches with a metal detector on private land.

Additionally, some regions may have specific regulations that further restrict the use of metal detectors. It is essential to consult local authorities or the Superintendence of Archaeological Heritage to avoid violating the law. ​

How much does a metal detecting permit cost?

In Italy, there is no national “permit” required for metal detector use. However, some regions have introduced specific authorizations for the search of certain types of relics. For example, in the Veneto region, for the collection of World War I memorabilia, a commonly known "patentino" is required, which is valid for 5 years. The cost of this authorization varies, but it usually amounts to around €200, including taxes and fees. It is important to note that this permit is specific to military relics and does not cover general metal detecting use. Therefore, it is advisable to check local and regional regulations to understand whether specific authorizations are required for the type of search you plan to conduct. ​

What is the fine for using a metal detector without authorization?

Using a metal detector without the required permits or in violation of current regulations may result in administrative and criminal penalties. According to the Code of Cultural Heritage and Landscape (Legislative Decree 42/2004), unauthorized use of a metal detector in protected or archaeologically restricted areas can lead to fines that vary depending on the severity of the violation. In some cases, administrative fines may start at several hundred euros and increase significantly if criminal offenses occur, such as failing to report findings of historical or archaeological interest within 24 hours. In such cases, criminal liability may also apply. Therefore, it is essential to thoroughly understand local laws and obtain all necessary permits before starting metal detecting activities.

Which materials are not detected by a metal detector?

Metal detectors are devices designed to detect metals through the transmission and reception of electromagnetic signals. However, not all metallic materials are detected equally well, and some materials are not detected at all.

Among the non-detectable materials are:

• Non-metallic materials: plastic, glass, ceramic, wood, stone, and fabrics. These materials do not conduct electricity and are not ferromagnetic, so they produce no detectable signal.
• Certain types of stainless steel (such as austenitic): although metallic, they have low conductivity and low magnetic permeability, making them difficult to detect with common metal detectors.
• Extremely thin metals or metals in small quantities: if a metal object is very small or buried very deep, it may not be detected, especially with entry-level devices.

For this reason, it is always advisable to choose a metal detector suitable for the type of search you want to carry out and to correctly adjust the sensitivity and operating modes.

How does the Garrett ACE 250 perform on the shoreline?

The Garrett ACE 250 is a best-selling entry-level product with which many detectorists have started practicing their hobby. It is a very good device, easy to learn, offering solid performance in terms of depth and discrimination, sturdy construction, and low power consumption.

However, since it operates on VLF/IB single frequency technology (6.5 kHz) and has a “fixed” ground balance system (like most lower-end models), it may struggle to work effectively on the shoreline due to salt mineralization or, in worse cases, also ferrous mineralization. In fact, single-frequency models rarely perform well in these conditions because they cannot balance both salt and ferrous mineralization simultaneously, which is possible with more expensive multi-frequency VLF models or Pulse Induction technologies.

In practice, you will often need to greatly reduce sensitivity to avoid a “concert” of false signals. In the worst-case scenario, the device may become so unstable that searching becomes impossible.

I read that detector X runs on 18 Volts while detector Y uses only 6 Volts... Does the 18V model detect deeper?

First, it should be noted that most products that operate at 18 Volts do not actually use the full 18V: 9 Volts power the audio and control section, while the other 9 Volts are used to generate the electromagnetic field. The voltage topic is quite complex and would require very technical explanations.

In practice, there are models capable of reaching excellent and above-average depths even when powered by just 6 Volts or less! The real difference often lies in the detector’s ability to efficiently manage the received signal, using proper processes such as:

• preamplification
• amplification
• demodulation
• analysis

rather than brute force in transmission. Another detecting myth is the performance improvement supposedly gained by increasing the power supply voltage.

It’s worth knowing that depth is related to voltage by a sixth power law! In other words, to double the depth, you would have to multiply the voltage by 64! And energy consumption increases by the 12^th power! That means, to double the depth, you’d consume 4096 times more power!

What’s the difference between a low-end and a high-end detector? Is the price difference justified?

Generally, low-end detectors are fairly easy to use, “turn on and go” type devices that require no special preparation or settings to start using immediately. They usually have “fixed” ground balance systems calibrated to a factory preset average value. This means that under variable mineralization conditions, they may become unstable and produce false signals.

Their discrimination ability is often fairly basic and rough, sometimes overly aggressive (to keep beginners from digging too much trash), and sometimes too lenient (which results in unnecessary digging). They are typically “quiet” machines that cannot be pushed to the limit, as this would cause stability issues, confusing beginners and making them lose interest in the hobby.

Advanced models, on the other hand, often include:

• advanced signal processing systems
• greater detection power
• manual or automatic ground balancing (which adapts to ground variations for more precise tuning)
• more refined discrimination
• better target separation
• superior mechanical components
• enhanced audio systems, etc.

These are definitely more powerful products, aimed at more demanding users who often want a more versatile and flexible machine.

Is it true that DoubleD coils eliminate mineralization issues?

DoubleD coils, thanks to their unique shape—resembling two opposing Ds—emit an electromagnetic field with a particular configuration.

While the most sensitive area of a concentric coil's electromagnetic field resembles a large rounded cone, that of the DoubleD coil is more like a narrow ship keel. As a result, the detection field volume is narrower compared to concentric coils.

In other words, if measured in cubic centimeters, the scanned ground volume is significantly smaller. This means less mineralized soil is analyzed, leading to fewer false signals from ferrous mineralization and better stability on mineralized grounds.

I’ve been told that coil covers make detectors more stable. Is that true?

Common coil covers are made of antistatic plastic and have no impact on the detector’s performance.

Their only function is to protect the coil from scratches and impacts that could damage its functionality.

Is a high-frequency detector better than a low-frequency one?

Electromagnetic fields generated by detectors using high frequencies (> 15 kHz) are better suited for detecting very small objects or metals with low conductivity (nickel, aluminum, small gold items).

Conversely, detectors using low frequencies (< 15 kHz) are more effective for larger objects or high-conductivity metals (larger gold pieces, copper, bronze, silver, etc.). Low frequencies also offer greater ground penetration, especially in mineralized soil.

I'm a beginner. Where can I search with my detector and where can’t I?

In our country, archaeological searches by unauthorized individuals are prohibited. It is not allowed to use a detector within archaeologically protected areas (even if not marked by signage!), and it is often also forbidden in landscape-protected areas.

Of course, when entering any land, it is good practice to ask the landowner for permission, even if the area is not fenced. On the beach, unless otherwise restricted, the use of metal detectors is allowed within the first 5 meters from the shoreline (public domain) or on public beaches. In concession areas, it’s best to first ask permission from the managers. In some coastal areas of Italy, provincial authorities may impose additional restrictions. I always recommend stopping by the local Harbor Master’s Office to request updated information.

Is it true that after heavy rain, my detector will gain some depth?

Soil moisture can influence the detector’s performance in two ways. The first relates to the reduced penetration of electromagnetic interference (such as from high-voltage power lines) into wet ground, resulting in less signal disturbance.

The second relates to the corrosion/oxidation effect on certain metals such as:

• bronze
• copper
• to a lesser extent, silver

which tend to form a slight “halo” around the object, slightly improving its detectability. However, don’t expect miracles.

I just bought a detector, which digging tools do you recommend?

The most popular tools are:

• shovels
• gardening hoes
• digging knives (commonly called “diggers”)
• “maleppeggio” (a regional digging tool)
• “Catania” hand hoes

Usually, the hoes are more effective on rocky ground where small shovels may struggle to penetrate. On the beach, perforated scoops are used (which allow the sand to fall away while retaining the target in the basket), made of sturdy plastic or metal.

They are available with short or long handles, depending on whether you prefer to dig crouched or standing. Obviously, for partial underwater searching, long-handle scoops are a must.

I’d like to try underwater detecting. Can I use any detector or do I need specialist equipment?

As previously mentioned, sea detecting primarily presents the challenge of salt mineralization, which not all detectors can handle efficiently. Moreover, ferrous mineralization is often also present, increasing the difficulty.

In addition, standard detectors can usually be submerged only with the coil and the shaft, but NOT the control box, which, as you can imagine, is not waterproof.

There are specific waterproof models, often multi-frequency or using Pulse Induction technology, designed specifically for this kind of use, and I highly recommend purchasing one if you want to focus on underwater searches.

What should I do if I come across an unexploded ordnance or potentially dangerous military item during a search?

First of all, there's one golden rule regarding the detectorist’s safety that should never be forgotten: “NEVER DIG IN THE CENTER OF THE SIGNAL!”. It’s always good practice to avoid digging directly at the center of maximum signal intensity. This helps reduce the chances of accidentally striking a potentially dangerous object while digging (it’s also good for preserving regular finds from damage).

When you start the recovery and realize you are dealing with:

• a bomb
• a grenade
• a mine
• another military ordnance

you must IMMEDIATELY stop digging! At this point, it’s best to mark the spot clearly to make it easier to locate. If you have a phone and there’s signal, move at least 50 meters away and call the Carabinieri to report the find.

NEVER ATTEMPT TO EXTRACT THE ORDNANCE! Only qualified military personnel are authorized to remove or safely detonate such devices. Always remember that military explosives are designed to wound and kill—never underestimate the danger, especially considering they may have become more unstable over time. To conclude, when in doubt, regardless of the object, don’t remove it from the ground.