It seems that there are countless terms and words used in metal detecting. It truly has it’s own vernacular in many ways. This glossary is meant to help identify what people mean when they say different words in the context of metal detecting.
Hot Rock – Generally a small rock that has metallic properties in it.
Pinpointing – A button that is on most metal detectors that help find exactly where the target is in the ground. It is most often used by holding down the pinpoint button and then scanning the ground in an X shape to find the center of the target. There are multiple ways to do this using the center of the coil, the tip of the coil as well as not using the pinpoint button but wiggling the coil back and forth sliding it back until the ringing stops. Note that the wiggle method only works with DD coils.
Discrimination – This is an option on the metal detector that helps block out audio tones of items you don’t wish to dig up. The most common example is not wanting to dig up ferrous or iron items. By discriminating against iron or ferrous items the detector will still “see” the item but will not give an audible tone telling you that the coil is passing over a ferrous object.
Notch Discrimination – Most VLF (Very Low Frequency) metal detectors have a Target ID Bar along the top of the screen/display that indicates what the target is most likely made out of that is below the coil. By discriminating one of the notches or sections on that bar you will no longer hear audio tones for targets that register in that target ID range. The ranges are generally in increments of 8 to 10 but can also be found in increments of 5 to 20. Note that this will block out audio tones for any object that registers in that notch range.
Target ID Discrimination – Considered to be much better to Notch Discrimination, this option allows you to block out a specific number or numbers. Metal detectors will have a target ID range sometimes from 0 to 99, 0 to 50 or even -9 to 40. If there is a particular target you do not want to hear on your detector then you can block audio for the specific number that the objects rings up as. For example, a pull tab that constantly shows up at a 64 or 65 as a target ID, both numbers 64 and 65 can be discriminated against so that when you swing the coil over a pull tab you will get no audio tone for it.