Steve Herschbach

The common test is to crush the rocks and pan the material to look for gold. This means you need to know the difference between mica, gold, and sulphides like pyrite when seen in the pan. From the HANDBOOK FOR GOLD PROSPECTORS IN WASHINGTON By WAYNE S. MOEN and MARSHALL T. HUNTTING 1975: "Many times the novice prospector is undecided whether the "yellow stuff" he is looking at is really gold or is something else. The yellow minerals that are most commonly mistaken for gold are pyrite, chalcopyrite, and golden-colored mica flakes. Pyrite, or "fool's gold," is heavy, but not as heavy as gold; it is hard and brittle and crushes to a black powder when hammered, whereas gold is soft (almost as soft as lead) and malleable and can be easily beaten into very thin sheets that are flexible (can be bent a number of times without breaking). Pyrite is soluble in concentrated nitric acid; gold is insoluble. Chalcopyrite, also sometimes mistaken for gold, is similar to pyrite in these properties. Pyrite commonly occurs as cubic crystals, but gold almost always is found in irregular shapes, and in those rare places where it does occur as crystals the crystals are always in intergrown masses. Tiny golden-colored mica flakes sometimes look deceptively like gold, but the luster of mica is different from that of gold; mica has laminations that can be split with a knife; and mica flakes, like gold, are flexible, but, unlike gold, the flakes are elastic, so that when bent they tend to return to their original shape. Gold is malleable, but mica is not; when mica is hammered it breaks up into numerous tiny flakes. Gold is heavy,· but mica is light. Thus, when panned, gold becomes concentrated in the very lowest part of the pan, but mica will be washed out of the pan, although because of its flakiness, it does tend to segregate somewhat from other light minerals. Mica fuses with difficulty; gold, pyrite, and chalcopyrite fuse easily in a blowpipe flame (gold at 1063° C.); and gold when roasted is odorless, but the sulfides, pyrite and chalcopyrite yield sharp-smelling sulfur dioxide fumes." Not super professional but that is why I like this video.... kind of how a lot of us might do it.... If the quartz has a lot of sulphides it was common in the old days to roast the material first to vaporize off the sulfur and other volatiles before panning. From Gold From Pyrites & Other Sulphides By E.H. HILL 1890: "Test for a Perfect Roast.—The object of roasting is to get rid of all the sulphur, arsenic, antimony, &c., that can be removed by the agency of heat, and to convert the iron, copper, &c., into oxides, thus freeing a portion of the gold and fitting the remainder for chlorination. A practical test of roasting can easily be made in an ordinary frying-pan, first coating the inside with a mixture of chalk and water and well drying. Mix the finely powdered ore with about its own bulk of fine charcoal; this is needful only when arsenic and antimony are present; still it helps to get rid of the sulphur and can do no possible harm. If the ore contains much sulphide of lead (galena) or sulphide of antimony (stibnite, antimony glance), add some fine sand, as without this addition the mineral while roasting would soon fuse, cake together, adhere to the pan, and ruin the assay. When all is thoroughly mixed, put the pan on the fire; stir well with an iron wire till the glowing ceases and no more sparks are given off; the assay will then appear of one colour, yielding to the stirrer like dry sand. Guard against too high a heat at first. If the roasted mineral is then examined with a magnifying glass or panned off in the usual way, a quantity of gold will be found free, ready for amalgamation." Note the process above may produce hazardous fumes. Use appropriate caution!

It's a slightly out of focus picture of a rock, mostly quartz and possibly smokey quartz. No way to tell without a sharper closeup picture of a fresh surface. Related post here....

This is without a doubt the strangest introduction of a new detector by a major manufacturer I have ever witnessed in 45 years. It reminds a bit of Troy, where Fisher made detectors for Troy Custom Detectors, but Troy did the design, marketing, and sales. Other than the Fisher name on the box, this is like an Alexandre Detector, made by Fisher but designed and marketed by Alexandre. As far as guesses... yours are as good as mine.

That’s just fabulous Merton, congratulations!

PI detectors designed to run off 8 AA batteries are at a distinct disadvantage compared to high power pi detectors like the GPX. There is a reason for that brick sized Lithium Ion battery on a backpack. Here an ATX struggles to see an item at 18” the GPX sees with room to spare. And it is a die-hard Garrett dealer doing the test.

Don’t doubt it myself. He is using a battery boosted version of the TDIBH which puts it closer to Pulsescan specs.

Something is in the works at First Texas, Garrett, Minelab, Nokta/Makro, White's, and any other detector company that wants to stay in business.

GPX is a high power PI. When you get yours working in 6 feet of saltwater let me know! 😂 I always thought it odd the worlds largest manufacturer of pulse inductions detectors has basically ignored the waterproof PI market. The floats like a cork SDC with its hardwired coil really does not count. I always wanted a GPX 5000 stripped to salt mode stuffed in a CTX 3030 housing. Then we would not be having this discussion. As it is the GPX is in a class of it's own so far and great for those who want to use one on the beach but not in the water. Frankly I don't want a GPX control box anywhere near saltwater for extended periods of time, but that's just me.

The ATX was my favorite Garrett ever. I finally sold it though and am boycotting Garrett over their refusal to make a Garrett LTX. I've had money burning a hole in my pocket for years to get a dry land ATX that weighs less and uses regular coils. But since Garrett refuses I'll take a 4.5 lb Fisher Impulse instead of another 7 lb ATX. If the Impulse has exactly the same performance as my old ATX and simply weighs 4.5 lbs instead of 7 lbs I'll be a happy detectorist. And if extra coils come out for the Impulse that cost less than $500 like ATX coils I will be happier yet. I have never been so frustrated with a company over a detector as I am with Garrett and the ATX. A truly fine PI circuit hobbled by the housing. If they had put it in a proper dry land housing with regular coils they could have put a real fire under Minelab in the gold prospecting market. The window for opportunity is now closing though, and the opportunity will soon be lost for Garrett. So sad. Anyway, that's my low bar. At least equal the ATX for performance, and weigh less, and I will be very satisified. If the Impulse AQ can't do that then Fisher will have wasted a lot of time and money.

Some people think a PI detects a lot deeper than a VLF and in the case of a very high power PI that can be true. But for what I would call mid-power PI detectors like the TDI SL or Garrett ATX, running off 8 AA batteries, the depth in low mineral ground running the same size coil is not much different than a good VLF. Assume just for illustration that a White's MXT with 12" coil and White's TDI SL with 12" coil get the same depth in mild ground on one particular test target. Now we have a magic dial and can turn up the ground mineralization. As we increase the mineralization, both detectors lose depth. The MXT loses depth at a faster rate however. I can't give you an exact ratio, but you can reach a point where the TDI now goes much deeper than the MXT. Yet the TDI is still getting less depth also.... it just does not lose as much depth as quickly as the MXT. It is also the case that with a PI if you have no ground balance filter engaged you can get the best depth in low mineral ground. Simply engaging the ground balance filter immediately robs a little depth. However, by engaging the control you do better in high mineral ground by comparison to the MXT. Whether you engage or disengage the ground balance circuit depends on the ground you are in. PI detectors do best by comparison to VLF detectors when ground conditions are the worst. The milder the ground, the less good a PI looks by comparison to a good VLF, to the point where you are better off with a good VLF due to the superior discrimination. Where I am in Nevada a White's GMT or Goldmaster 24K or even MXT is a better all around gold prospecting detector than a White's TDI SL in a lot of the desert soils due to the mild ground conditions, and the hot VLF detectors can detect tiny gold nuggets a TDI can't see even in direct contact with the coil. To sum up, the Impulse AQ will shine best where beach conditions are the worst. In general sands derived from volcanic activity and granitic rock, with high magnetic mineral content. People in mild sand derived from coral... not so much.

I have to tell you Fred that “I’m not very smart” self talk bothers me. You are not dumb so stop that nonsense. The gold prospecting version of the Impulse is really barely more than a rumor. People in the know say testing is underway so we know it’s pretty much real, but even detectors undergoing testing often never come to market, so it is not 100%. We assume it will share the general look and feel of the Impulse AQ, but that is just an assumption. Personally I think making any detector without wireless these days is not forward thinking. Even the Impulse AQ would have benefitted since the majority of users will probably be beach walkers and shallow wading types. The fact is the Impulse AQ is not wireless and Fisher has not made a wireless detector yet so it’s a fairly low bet I’d say for the prospecting model. Maybe Alexandre can reveal more.

How do you know what the targets were that you did not dig up? Do you believe 100% of the targets you did not dig were not gold? That you have a 100% accuracy rate? If not, what percent is acceptable to you? If you skip 100 targets is it ok for ten of those to be gold? Five? Two? I’m not being critical here, just curious. I have skipped a lot of targets over the years for various reasons, but I am certain that I have left gold in the ground as a result. I know this because I have dug plenty of “nail signals” that turned out to be gold.

Why use a PI on a low mineral beach? Unless you have an extra large coil there generally is no real depth advantage over a good VLF in low mineral ground and a VLF has far better discrimination. I don’t even see the sense in testing one of these in Florida, as is being demanded by many people. This is a detector for the west coast or Hawaii, not Florida white sands. Florida is one of the worst possible test locations I can think of.

It’s a PI vs VLF thing. In low mineral beaches there is no huge depth advantage for a PI. A pulse induction loses less depth in highly mineralized conditions and so has a good depth edge if that is what you have to deal with. With a PI the price you pay is digging way more trash.... basically dig it all. VLF you have discrimination. Florida white sands.... not much depth advantage to PI. West cost beaches and Hawaii, there is a depth advantage. And consider whether you like digging everything or want discrimination.

It would be great at some point to hear if you end up preferring one or the other. Happy Hunting!

I might try it myself. I kind of regret not buying one of those custom Russian rakes when they were for sale. They were not that expensive and I can see how that zig zag cut would catch the chains. Beach Rakes

Rocks don’t always float to the top. Many sink. It just depends if they are dense or not and the composition of the finer material. And panning involves washing off the light stuff, leaving rocks behind.

New anyway. Here is a used one for $700

I agree Alain about a chart, and I have a good start on one, but without actually having a detector it's only educated guesswork on my part based on what Alexandre and LE.JAG have posted so far. The one I posted was just a quick and dirty illustration. Hopefully they or Fisher will do something official before release, otherwise you can be sure people will eventually construct some at a later date. I was hoping for one detector that would do both land and sea, something I liked about my ATX. To be honest I think Fisher will have a hard time making a detector more powerful than a GPX 4500 or GPX 5000 let alone a GPZ 7000, and few people who already own those are willing to give up any power, even if the detector is lighter and costs less. Minelab means gold prospecting to a lot of people so Fisher has a tough road ahead there, and they have let Minelab have lots of advance notice what to expect.... I doubt the engineers down under are asleep at the wheel. The AQ model however has only a couple detectors, the Garrett ATX and Beachhunter TDI, that are truly equivalent product. For me at least, having none of the three at the moment, the choice is pretty clear. I am fed up with 7 lb detectors that have $500 coils, and the Impulse, using the TDI as a starting point, simply has to be better, or Fisher has wasted a lot of time and money. I sent Dave Johnson a TDI (big box version) years ago and Carl worked at White's so they know what they need to beat to succeed. Fisher Impulse AQ vs Garrett ATX vs White's TDI Beachhunter

Every one was a gold nugget.... until it was not!

Too bad it is such a poor translation to video, but the information presented is still just as good.

Hi Alain, I went ahead and deleted the post and the chart. I put several disclaimers in the post that the chart was for conceptual purposes and was not intended to create an absolutely detailed, accurate, and definitive target response chart. I was assuming some degree of interpretation/interpolation by the viewer. Part of the problem is it is being taken out of the context of everything I have posted on the subject in the last ten days. I explained previously in this thread ahead of the chart that ferrous covers the entire range so I obviously agree with your conclusion since I have explained that exact thing so people would know it to be the case. I included both ends of the ferrous range in the chart and did actually include a portion of the bottle cap range that you must have missed. Long story short since the chart is being taken as definitive instead of conceptual despite the disclaimers, leaving it up is misleading or confusing people, and so deleting it it is probably for the best. I halfway knew when I posted it this was going to happen.

It’s almost enough to make me want to get an SDC and gut the thing out, put it in a real detector box and rod combo, so I can use coils like this the way they were meant to be used. I’d love an SDC configured like a Eureka Gold with a set of coils like this.

USPS Ground is a lot less expensive but can take forever. Like weeks instead of days if you get unlucky. Apparently they wait until they get a full truck. And it can only be done in person at the Post Office. They must not like people using it because it is not offered as an online option. I generally use Priority Mail but from Nevada I have learned that going East, once the box crosses the Mississippi, the cost triples. Seriously, an $18 box will go up to around $60. It’s become a huge issue when selling stuff online now.