I was sent this coil for free to use and keep by the manufacturer many months ago with no expectations of reviews or anything else, and I had intended many times to test it in Nevada for my own personal use, but work kept delaying me and I never made it. But I was able to finally get free from work and give it a solid 12 hours of run time over 2 days in Arizona since it's winter now. Soils are mild, few hotrocks (more on that in a moment). 40-50F degrees out. Mostly shallow, rocky washes or hilltops I've pounded with the stock and 17" X Coil (as well as a 4500). I consider these spots flogged and dead for my purposes, and so great places to see if new products can find missed gold. My observations were as follows:
This coil (as expected with a smaller coil) was noticeably quieter than the 17" coil and the stock coil. I was able to bump my threshold up 8-10 points and still had about the same threshold chatter as I did with the 17" coil. I usually run 18 sensitivity here because I like a very stable threshold and EMI can be an issue, but I bumped up to 20 sensitivity with no problem. The coil ground balanced ok and I ran in auto which seemed to work fine. This coil loves hotrocks, as would be expected when you are running a smaller, more sensitive coil. I was finding hotrocks deep, shallow, and in places I considered more or less hotrock free in the past. Conversely, I hope it will do well in salt, which I hope to test this summer in Nevada. This coil is bump sensitive This coil is sensitive to a lot of vegetation, particularly sticks/twigs and grasses. I'm unsure if it's detecting them or bumping them. This coil screams on tiny nuggets just out of range of the stock coil. It gives decent signal on edge of detection, tiny nuggets that I missed with the 17" coil. The light weight made me very much more prone to lift up and detect side walls, benches, and pick up and poke/prod into just about any place I encountered, from beginning of day to end. The weight didn't fatigue my arm after a half day of swinging, 5 or 6 hours. Much of that time was without a bungee. This coil eminates a faint, very high pitched squeel or buzz if you get your ear close to it Overall, detecting with the GPZ feels a lot more pleasurable and less like fighting your equipment with a coil of this size and weight. I've mentioned it in prior posts, but take my word from experience now - it's not the weight of the GPZ that causes problems, it's the coil. And this 8" coil is almost the perfect weight to counterbalance the GPZ with the shaft fully extended - ie, this is the coil weight the GPZ should have been designed for. I'll take another pound on the control box no problem, but add 100 or 200 grams onto the coil end, that causes fatigue. Swinging the GPZ with this coil (or any coil of this weight) is a pleasure and not oppressive. The bump sensitivity I'm guessing is a relic of trying to cram so much wire into a tiny space that might not be meant for it, as I get the feeling that this coil is pressing the limits of how small a Super D can be built. But it does mean that I have to slow down and really concentrate on not hitting rocks or vegetation, which ends up being ok because this is a cleanup coil where I am going slow anyways.
I expected to find a handful of faint, edge of detection signals I had missed with my other coils. But other than a couple nuggets, almost all the signals were bright, some even loud, and all pretty obvious. Even right out in the middle of the wash. This coil hits hard on tiny stuff.
I haven't compared it to the GB2 or Gold Monster, but I found stuff down to 0.06-0.07 grams and they were all great signals. Pinpointing these tiny targets with the coil edge can be difficult as the center of the coil is more sensitive. And they are too tiny to register on my pinpointer, especially the porous and not flaky ones.
And that is why I think I missed all the nuggets originally which I later found with the 8" - its a lot easier to get the center of the coil over more of the potential ground, especially with obstructions in the way. In the end, I didn't find a lot of missed nuggets in nooks and crannies, most of them were simply next to a rock or other obstruction like a bush which I was able to get the center of the 8" much closer to.
Overall this seems like a good coil for working steep areas (Colorado comes to mind), surface patches, tight washes, and banks/vertical surfaces. The bump sensitivity is the only real major downside, so a slow and controlled swing is important with this coil I think. If NF doesn't end up releasing some critical sizes of coils and new detector releases make the GPZ cheaper (and less risky to make an adapter) then serious detectorists may want to give X Coils another thought. Because right now I can't help but feel like with these coils I am running a new detector that no one else has access to in a way, and I'm somewhat surprised more hard detectorists/enthusiasts haven't availed themselves of this opportunity. But, in the same respect I'm happy, because my time is slim and I haven't had a chance to put them over a lot of places I know others would have flogged to death already. My favorite coil by far is still the 17", but if this 8" (and the 10") perform well in NNV then I may change my mind on that.
Here are the nuggets I found (weights are estimated) and my recollection of why I thought I missed them originally with all my other equipment but then found them with the 8" X Coil:
Test Wash 1, less than 0.1 gram, too deep for other coils
Test Wash 1, 0.08 grams, next to a rock and slightly into wash bank
Test Wash 1, 0.12 grams, from a boot scrape and I had given up finding this with the 17" for some reason
Test Wash 1, 1+ gram, next to a rock and oriented vertically in a bedrock crack, not sure why I didn't hear this on at least 6 or 7 previous passes since it's right in the wash, but it didn't produce a diggable signal with other coils/machines
Test Wash 1, .2 grams, in a little ring of rocks, was only a few inches deep though
Test Wash 1, .15 grams, too deep/edge of detection, or too close to rocks
Test Wash 1, 0.12 grams, no idea, great signal and should have found before
Test Wash 1, 0.15 grams, in side of bank, arm was probably always too tired to raise the coil up there
Test Wash 2, 0.12 grams, no idea why it was missed before, right in middle of wash
Test Wash 2, 0.3 grams, 2ft up wash side
Bench patch, 0.3 grams, next to cactus, too deep/edge of detection?
Bench patch, 0.08 grams, too deep/edge of detection
Bench patch, 0.06 grams, edge of detection
That was all of them. Smallest was 0.06 grams and very porous and almost on surface, largest was like 1.1 grams but I forget the exact weight. All total was a little over 4 grams out of severely beat up washes and a patch. Not much, but it did pay for my gas down here at least.
I think once stuff gets below 0.15 grams, it's not really worth my time to chase on general principal. But when you need to grind out some finds for gas, food, whatever, and if you have a lot of patches that produced more than 5 or 6 stray nuggets, then this little guy can probably pop up a few more when you really need them.
A mate that was lucky enough to get into Western Australia early this year has been having a good time, he got a 20" spiral x-coil on the Zed now because he was getting big deep gold and some of the holes he was digging with 17x12 spiral at up 900mm and he reckoned there was deeper gold.
This one in the video is not one of the deepest but for the size nugget it is a reasonable dig just the same.
I was sent this video, the x-coil runs very nicely in the wet ground, just remember these coils are not water proof so don't submerge them.
I'm not sure if the nugget was stuck down deep or kept sliding back into the hole from the water, but anyway what impressed me was how well the 10" x-coil was handling the wet ground.
Anyway I just though I would share the guys video with you all.
Finally got out again with the 15" x 10” X-Coil. It ran really quiet and smooth continually in High Yield, Normal, at Sensitivity at 20. Found 10 small nuggets for a total weight of 4.55 grams. They were between 5 to 8 inches deep in a California pine tree area.
The X-Coils work great, but the 15 x 10” is now the go to coil.
Have a good day,