Informal Testing Of The GPZ Vs The 5000 On Mossy, Wiry Gold

[Reno Chris]

So I was out in the goldfields of California yesterday with Steve Herschbach and another friend who is a detector dealer. We did some quick tests comparing the 5000 and the GPZ on mossy, wiry gold that we had found previously. These were pieces from both Nevada and California.

The smaller of the two nuggets shown in the attached photo weighs 3 grams and with an 11 inch mono set on maximum gain of 20, it was totally invisible to the 5000 - even when it was touching the coil. The detector made no response whatsoever. The GPZ on the other hand could see it at about 10 inches, and it was dug from a pounded patch that has seen many GPX detectors (including mine) at a depth of about 6 inches. The GPZ was set for difficult soil at only 12 sensitivity. So what is the performance improvement over the 5000 when one detector is blind to the piece and the other sees it at 10 inches? Mathematically speaking, it is an infinite improvement - a whole lot more than 40%.

The larger of the two pieces pictured in this post weighs 18 grams and the 5000 could see it to a maximum of about 10 inches. The GPZ could see it at 20 inches, and it was dug with the GPZ at about 18 inches. Going from 10 inches to 20 inches is a 100% improvement - double the depth of detection and also a lot more than 40%.

We also tested some specimen gold Steve had with similar results - the 5000 could not see the smaller specimens of a few grams size. 

Of course we all know that the 5000 performs very well with more solid nuggets and specimens. I have found lots of gold with my 5000, it is an excellent detector.

However, the GPZ is a gigantic improvement over the 5000 when it comes to mossy, wiry, prickly, specimen and other similar forms of gold.

Some may say there is not much of this type of gold out there. I would say in response, if most of us are using detectors that perform poorly on that type of gold, how does the fact that we don't find much prove that it doesn't exist? Truth is that there is loads of specimen gold out there and I think the GPZ will be finding a lot of it in the coming weeks and months.

Geologically, many of the places where the nugget gold is truly deep are locations where the patch is sitting as a residual over a vein, and having a detector optimized for specimen gold would make very good sense.

Some hard rock deposits tend to produce this type of gold. Smart prospectors with GPZ detectors will be using this knowledge to their best advantage.

For me, I have been doing research to find places which produce this type of gold and I intend to be using the coming months to leverage this performance increase to the greatest extent.

[IdahoAl]

Chris thanks for the post and info...I wonder if a Garrett ATX would see them??

[jasong]

 

Some may say there is not much of this type of gold out there. I would say in response, if most of us are using detectors that perform poorly on that type of gold, how does the fact that we don't find much prove that it doesn't exist? Truth is that there is loads of specimen gold out there and I think the GPZ will be finding a lot of it in the coming weeks and months.

 

 

Been thinking the same thing and unable to phrase it succinctly like you did. I'm kind of surprised so much attention in the detecting world has been specifically on just old patches and not taking the Z to places with potential for entirely new discoveries where the GPX was severely handicapped. There are a lot of places in the US where it could really shine. One problem is that some of them produce extremely recognizable gold for others who do the research so posting results could be uh...problematic and we may not be seeing a lot of results online by the serious prospectors. 

[Shelton]

Now the best way is to comapre it to ATX and SDC. And we have clear, wide view on top prospecting market machines.

[Steve Herschbach]

Much has been made of the Minelab GPZ 7000 ads and the depth comparison claims. People of course see what they want to see and an amazing number of people seem fixated on 40% while forgetting the "up to" part of the claim.

The is a huge difference between a detector going 40% deeper than another detector and "up to 40%" deeper.

If I say "there are people in Los Angeles that are up to 7 feet tall" how many 7 foot people do there need to be in LA for that statement to be true? That's right, just one. Similarly, for Minelab to claim that the GPZ can go up to 40% deeper than the GPX 5000 they only have to prove one instance for which that is true.

I warned people at the Minelab dealer convention that the 40% thing was going to cause problems with people wanting to believe 40% across the board versus what is actually being said. I also said that I personally believed from my own experience that a larger number, like 100% or 200% was just as valid in the context of "up to". Doc was at the convention and picked up on what I said, and it made it into a short lived post on Rob's forum.

Still, seeing it again yesterday was a shocker in that this time we were using a GPX 5000 with 11" mono on Sensitive Extra with Gain cranked to 20, and it still could not see my specimen when rolled on the coil right over the edge next to the coil windings. Yet I had banged this specie out fast and sloppy with the GPZ with no trouble at all. We compared using the GPZ in Difficult and the GPX cranked to the max just to make the comparison conservative and still it blew the GPX away. Forget percentages, it is the difference between finding and not finding.

I had wanted to do the test because I had used a GPX 5000 with 14" x 9" Nugget Finder mono in Sharp mode, Gain 16 when I had originally hunted the ground and found nothing, only to find gold later with the SDC and GPZ. I wondered if Sensitive Extra would have made any difference. It just was hard to believe the GPX could not find this stuff.

Chris and I debated whether to post about this at all. I almost did last night and then decided not to. You can lead a horse to water...... go and look again if you have not already at the second half of my first official post on the GPZ. I made the post knowing I would be able to point at it for years and say "told you so!"

Here is the 2.7 gram specimen that is invisible to a GPX 5000 with 11" mono on Sensitive Extra and Gain 20. Detectable above the ground at 6-7" with GPZ 7000 in Difficult ground setting, High Yield, Sensitivity 12.

UPDATE: gold was found as described in this new thread http://www.detectorprospector.com/forum/topic/742-my-eureka-moment-the-rest-of-the-story/

I have a few days hunting in a few different locations now with the GPZ since selling my GPX and not for one second have I regretted the decision. If anything I like the GPZ better each time I use it. It is less a machine I instantly like than one I learn to appreciate over time.

[fredmason]

When Jc walked the earth and worked miracles there were naysayers and doubters...it is the normal condition for many and that will always be true.

 

Nice gold and comparison testing, thanks

fred

[vanursepaul]

cool

[Steve Herschbach]

The SDC sees this kind of gold well, but is limited by its small hard wired coil size in the maximum depths it can attain. My ATX does see this gold better than the GPX but not as good as the SDC or GPZ.

[flakmagnet]

Very interesting series of posts guys.

I cannot wait to begin to actively learn some of what you talking about.

Thanks for taking the time to clarify some of the details under discussion,

you are rapidly earning the trust of a lot of your readers.

[LuckyLundy]

Now I need a patch full of that gold...lol. Great read guys! Keep the great work up...Until the next hunt

LuckyLundy