To piggy back on Steve’s post about the different types of metal detecting, I want to talk a little bit about relic hunting. In the United States, relic hunting often refers to the searching of war relics. Famously, people look for ammunition from the Civil War and for personal items from the soldiers who fought on said war. However, relics can be just about anything, even coins if the coins are part of another object. In my personal opinion, a relic is any object from times past.
And when it comes to metal detectors, any detector can be used to hunt for relics but there are some specific attributes that will make some detectors better than others when it comes to recovering relics
Relic hunters need to discriminate iron only, as a relic can be made of any material (even iron!) so the type of detector needed for relic hunting ideally should sacrifice discrimination for depth and for the ability to see through soil with a high mineral content.
Pulse Induction (P.I.) detectors fit this bill nicely. Detectors such as the Minelab GPX5000 or the White’s TDI are detectors that can go very deep and are not bothered by minerals in the soil. Since a relic hunter looks to dig everything except iron, the lack of metal discrimination is not a problem so long as the unit can successfully discriminate iron. One can readily see that one these units would not be suited for hunting coins in a city park because the P.I. machine would not be able to discriminate foil, pull tabs, or bottle caps.
Lately a Very Low Frequency (VLF) detector has become popular in the relic hunting world and that is the Bulgarian BlissTool. Similar to a P.I. machine but less expensive, the BlissTool is equally unsuited for city park metal detecting.
If you want to emulate one the machines mentioned with your detector, try hunting in All Metal Mode or Zero Discrimination mode (they are two different things). You will be able to reach deeper but you will also be forced to dig every beep you get.
Here in Wichita, relic hunting is not a very popular sport but that doesn’t mean that you cannot find some pretty cool relics. To find relics with your metal detector will require that you expand your definition of a diggable signal to include more mid tones and to not rely so much on your Visual Discrimination Indicator (VDI) numbers. It will take some practice but eventually you can get used to it. So relax and sharpen your ear, and you too will be finding cool relics in no time.