Treasure Cove metal detector Metal detectors


Q:  How deep can a metal detector to detect coins and other metal?

A:  Most metal detectors are equipped to detect coins and other small size metals at depths of 8 to 12 inches, which will vary depending on the size and ally of the metal.  To detect in depths beyond 12 inches will require a larger coil.  However the larger search coil will lose the sensitivity.  For example, a 15 inch coil will detect large metal items at depths up to 4 feet; however a single coil will detect single coins, whereas a larger coil cannot. 
The depth at which a metal detector can identify varies with many factors.  Generally speaking:

  • The skill level of the person using the metal detector.  The better you know how to operate your metal detector and understand the detection signals will increase the depths.  Additionally the speed at which you sweep the detector across the ground will affect the depths at which you are able to detect.
  • The size and shape of the metal as well as the alloy levels all play a factor in detection depths.  The way the metal is positioned in the ground contributes as well- if a greater surface of the metal is facing up, it will be detected at greater depths.
  • The condition of the soil and the levels of minerals present in the soil.  If the soil has high mineral levels, it will be more difficult for the metal detectors to cancel the interference of the magnetic and/or conductive properties.  Additionally, if the soil conditions are very poor, detection depth will be reduced.
  • The size of the search coil.  The larger the search coil, the deeper one can detect larger metal items.  Smaller search coils provide better sensitivity to small metals (i.e. coins and jewelry) in high trash areas. 
    • Properly using a metal detector with an 8 inch search coil, these depths should be achievable:
      • Dime to nickel sized item- 4 to 8 inches
      • Quarter to half dollar sized item- 6 to 12 inches
      • Dollar to jar lid sized item- 8 to 16 inches

Q:  What types of items can I unearth with a metal detector?

A:  Any type of metallic objects.  For example- gold, silver, bronze, nickel, brass, copper, aluminum, tin, etc.  Metals detectors cannot detect non-metallic item like diamond, pearl, gemstone, etc.

Q:  Are all metal detectors the same?

A:  Metal detectors have different technologies, features and performance characteristics depending on their intended use.  There are basically four types of metal detectors:

  • General purpose- the hobbyist looking for coins and jewelry
  • Gold searching (natural gold)
  • Underwater
  • Deep searching for relics and caches

Some metal detectors are designed specifically for one type of searching.  For example, the general purposes models are not typically designed to detect small grain sized metals, however gold searching detectors can. 

Before purchasing a metal detector it is important to determine what type of metal you want to be detecting.  All of the manufacturers make several different models of detectors, and you want to purchase one that fits your searching needs.

Q:  What is discrimination?

A:  Discrimination is how a metal detector is able to determine what type of metal it is detecting.  This allows for you to only dig up the type of metal you are searching for (e.g. gold and silver).  Some metal detectors have both visual displays and audio (headphones) types of discriminators.

Q:  Can a metal detector be set to only detect gold?

A:  No.  There are too many variables with the exact amount of alloys and sizes to be able to detect only gold.  Gold can be mixed with silver, platinum and/or copper, which will all read differently on the discriminator which is why it cannot be set to only detect gold.

Q:  What is operating frequency mean?

A:  Frequency is the number of times a signal is transmitted and received by the metal detector every second.  It is measured in kHz (kilo hertz).  So if you are operating your detector at 7 kHz will transmit and receive 7,000 times per second.

Lower frequency metal detectors offer better sensitivity to silver and copper, in addition to better overall detection depth.  Higher frequency models offer better sensitivity to smaller metals and natural gold. 

Q:  What is the difference between 2-filter and 4-filter metal detectors?

A:   2-filter and 4-filter are used to describe the amount of electronic circuitry a metal detectors uses with both discrimination and elimination of minerals in the ground.  A 2-filter model of detector will works best in conditions where the mineral levels in the ground are low to medium.  A 2-filter will also offer a fast response when objects are close together in trashy areas.

A 4-filter model will detect at greater depths in highly mineralized grounds.  They also offer greater audio discrimination and more advanced features.  A 4-filter model of detector will also be more expensive than a 2-filter.

Q:   What is Target ID and how does it work?

A:    In addition to audio discriminators, many models of detectors have displays that indicate the possible metal that is detected.  With a Target ID display you will dig up less trash, because once an audio signal is heard, the display will give you an independent, second opinion. 

The ID display is a very accurate measure of the target's electrical phase response, but unfortunately many targets have identical, or nearly so, target responses. 

Q:   Why are there different sizes of search coils? 

A:    The standard search coil that the metal detectors are equipped with is optimum size for most hunting.  In extremely trashy areas, a smaller coil (4 inches to 7 inches) will get better results.  And if you get into a relatively clean/trash-free area, a larger coil (11 inches to 15 inches) will usually yield better depth and a wider area; although with a 15 inch search coil sensitivity to coin sized targets decreases. 

Q:   Do I need headphones?

A: The only model that requires the use of a headphone is the Underwater/Scuba. Headphones are optional with the other models as each detector has visual feedback.

Q: If you test your metal detectors for lead and there is no lead found in your products, then why do you add a Prop 65 warning to your products?

A: Our factory functions under very strict standards to ensure that lead is not used in the manufacturing of our metal detectors. We annually test each model to ensure that our factory is in compliance with Prop 65. However, human error can always occur and we cannot 100% guarantee that on a rare occasion one of our metal detectors may accidentally contain trace amounts of lead. It is our belief that we should continue our testing process however we should also warn the public that however unlikely it is - there may be trace amounts of lead or other chemicals present that are known to cause cancer, birth defects or other reproductive harm.

Q: How much of the metal detector can go under the water? Can I use it in heavy rain?

A: The only model designed to be completely in the water is our TC-7010 Scuba Underwater / Surf metal detetcor. All other models are only waterproof up to the searching coil. You can only safely put the search coil into shallow water, not even the aluminium pole should be submerged. As for heavy rain, though we prefer you not use any model in the rain, all models can be used in light rain, but not in heavy rain.