Overview of Metal Detector Types
Gold prospectors have two basic choices when metal detecting for gold. There are very-low frequency (VLF) metal detectors, and there are pulse-induction (PI) metal detectors. Both types can find gold, and each has their own place in the goldfields.
(Note: The new GPZ7000 uses a completely new technology, but it operates pretty much just like a PI detector, so we won’t worry about that in this article).
PI detectors get the most Attention
These two detector types each have advantages and disadvantages, but most serious gold hunters have gravitated toward PI detectors in recent years. And this is for good reason… PI detectors run much quieter and smoother than VLF detectors. They do an exceptional job of canceling out hot rocks and ground noise, which VLFs aren’t so good at.
I use a PI detector for about 90% of my gold detecting. Their ability to cut through the ground noise gives them a considerable depth advantage over VLF detectors. Of course depth is very important in many places, because the goldfields have been hunted hard over the years. If you are hunting in a “pounded” out area, then a tiny extra bit of depth can result in a nice nugget that other detectors can’t hear.
Serious Gold Hunters Use Both a PI and a VLF
Pretty much every serious gold hunter I know is using both a PI and VLF detector. PI detectors are still the go-to detector for most situations because of their depth advantages, but don’t throw away those VLF detectors just yet.
VLFs are “Old” Technology, but they Still Work
VLFs are much older technology. Lots of the better-known goldfields were already “cleaned out” with VLF detectors before PI detectors were even invented. Then PI detectors came along (over 20 years ago now) and prospectors were able rework old areas again.
In these heavily worked areas, you would think that a VLF detector would be about worthless. However, they still have some advantages over PI detectors that will produce gold even to this day. Even those $5,000 PI detectors will miss gold that you can only find with a VLF.
VLFs are still better than PI detectors when it comes to small gold. PI detectors are great for punching deep on good-sized nuggets, but they aren’t all that great on small bits of gold. This is especially true on flaky, crystalline pieces of gold. For some reason, these nuggets can be virtually “invisible” to PI detectors.
Some of the newer PI detectors (the SDC2300 in particular) have improved considerably and hit really well on smaller gold, but VLFs are still king.
Small Coils on Bedrock
A VLF with a small coil is killer on bedrock because you can get down and work all those nooks and crannies with ease. The Fisher Gold Bug 2 with 6″ coil is absolutely deadly on shallow bedrock, but just about any high-frequency VLF will do well on bedrock.
All VLFs have discrimination capabilities that give you an idea of what’s in the ground before you dig. This can be helpful, but I recommend you dig all targets most of the time. Once you really understand your detector you can pass on some targets, but most of the time I’d tell you to dig, dig, dig!
New Models do Have Improvements
Even though VLF detectors are “old” technology, they still work, and in some situations they work really well.
Many new detectors that are coming out still use VLF technology. There are two that came out this past year that are really great gold detectors, and if you are looking to buy a new VLF gold detector then I would recommend one of these:
Both of these detectors work really well. I use to think that it would be hard to improve the Gold Bug II, but most of the serious prospectors that I know have upgraded their old detectors and are using on of these two detectors now.
Yes, VLF detectors are indeed “old” technology, but they still work well in the right situation. Plus they are way cheaper than PI detectors. If you are just starting out and looking for a good detector don’t hesitate to buy a VLF detector. They are still very capable of finding gold nuggets.