wirelessguy

http://meteorites.wustl.edu/ A better launch page

http://meteorites.wustl.edu/what_to_do.htm#actlabs Salutation at this very informative website us below: (and yes, do click on those read this and this links too) Prepared by: Randy L. Korotev Department of Earth and Planetary Sciences Washington University in St. Louis Please don't contact me about the meteorite you think you've found until you read this and this.

This is why I read Detector Prospector for my news these days! I need good stories like this about humanity to help "positivate" me of all the bad news.

This is a very informative thread. Thanks Steve. Does anyone have a metallurgical explanation why some some steel indicates non-ferrous when it rusts? I find this most often on some forms of steel wire or cable that has rusted to the core, often disintegrating when you dig it.

In more fishin' analogies : My Uncle Joe's common line, "the catching wasn't so good today but the fishing was good". Fishing and Catching are different elements of the activity. You gotta like fishing (even if you're not catching) to have the tenacity to keep on "spend lot's of hours doing it" so that over time it adds up to catching. You have to overall enjoy - the environment, the prep, the travel, ... non-catching stuff.

"This 6 ounce piece could not be heard with a GPX 5000 with a 25" mono attached no matter what settings we tried. This is just some of the gold that was found with the GPZ 7000 and a large coil during development. If the gold is there the GPZ 7000 and GPZ19 combo will nail it." -JP cut and paste quote from JP from his FB site in association with the "giant hole" photo he posted above. https://www.facebook.com/JonathanPorter.TheOutbackProspector/posts/1783833608524470

I talked to two USA Dealers. They have been given no information yet from Minelab USA about price and delivery for the GPZ 19. They were both apologetic that all they have is rumor. They both learned of yesterday's announcement when customers started calling.

http://www.infomine.com/careers/ ballardbrandon, I find infomine.com to be a good resource for all things mining.

Within a year, two at most we'll be in the midst of another worldwide recession. It will be fueled by the weakening economies of China and Europe, yet will be felt in North America, too. Historically, a lot of money goes moves into gold to weather the storm of such events. So, gold is on an upward trend until the world comes out of the next recession. I'm still a working man so don't take my economic advice. The above is from the smarter people who now manage my meager retirement account since I've quit squandering it

Jasong et al, My experience and that of a detecting buddy with the Zed in a USA hardrock environment is that 100% of our confirmed gold finds went high-low in HIGH YIELD/NORMAL. Some switch to low high with other ground type settings, some don't. However, my wife's large 18kt wedding band is low-high in HIGH YIELD/NORMAL in an air test. Our gold is typically 85% Au 15% Ag. Our various types of hot rock can sound high-low or low-high. I started a thread on this subject in June 2015, http://www.detectorprospector.com/forum/topic/1057-gpz-7000-discrimination/ and am pleased to find more great commentary in this thread. Sorry to be late to your thread. I have believed (from reading MD theory and discussions with experts) the gold purity is less the factor than gold size / shape for the phase of the return signal and hence tone. I have confirmed this with tin foil tests, that is I can cut small pieces of flat tin foil and on HIGH YIELD/NORMAL it rings high-low. I can cut larger pieces and/or shape some into a ring shape and the Zed sounds low-high on HIGH YIELD/DIFFICULT. Having read this thread I understand Steve's point on conductivity of object relative to ground balance point and I'll just have to ponder that some more. "Digging" in our environment almost always involves explosives so we go through a process to qualify a gold target. My normal hunting routine is to go prospecting with the Zed. Mark interesting spots to come back to with other MDs and my partner to help in discerning gold/hot rock. I have come to use the Zed high-low trend as a PART of the target validation process. If it sounds low-high and I can visibly see known hot rock rock structure at the site of the target or a lot of it in the close vicinity my analog brain moves toward judging hot rock. If I get a low-high in visible quartz, I'm thinking (well, more hoping) for a large bonanza and come back with more weapons. A low-high has not yet turned out a bonanza or any amount of gold. Yes, I've walked away from quite a few low-highs. The Zed has sounded high-low on multiple finds that ended up being equal in ounces to many, many of my wife's wedding rings. These were natural deposits spread over a volume of quartz. Again, my wife's ring sounds low-high in an air test.

Super informative thread. Thanks Steve, Jonathon and other contributors.

I'm mostly a 1 type. Rarely use headphones

NVChris thanks for documenting your Zed repair story. Nov 12 to Dec 2 = 20 days out. I have an RMA from Minelab Chicago for the same Zed pixel issue yet have not sent it in since I don't want to be without it 3 weeks. They quoted me "2-3 weeks" for the turnaround. My display never goes blank and the thin vertical line is about 4 mm wide and does not interfere with any critical characters and is not getting worse. Been this way about 3 months. A friend's Zed has the same missing columns of pixels issue and his is continually getting worse - more vertical columns of pixels going black. The pixel issue and broken plastic footrest are the only problems I've had with my Zed. I don't do gentle well. Mine has seen a lot of abuse to more parts than the coil cover.

good find, thanks Steve

The first thing I looked for when reading the Minelab GPZ 7000 software update brochure http://www.minelab.com/__files/f/286800/GPZ%207000%20Software%20Update%20Brochure.pdf was to see how I could "go back". In other words, how can I reinstall the original software (ver 1.08-57) in case I don't like the new software. Since I cannot find any 1.08-57 file nor instructions on such, I have decided to let my good virtual friends on the Detectorprospector.com forum report on their experience with the new software before I make the leap. Particularly interested in buddy pairs with two Zeds run new and old software over known troublesome ground, since that is what the improvements are all about.

Great thread! Steve, why do you pack your scale? I understand all the other prospecting, safety and all day comfort things you and others carry. I strive for light weight so for me a scale is something to leave in the truck unless curiosity can't wait and it's worth the - admittedly small - weight. Or, is there something other than instant gratification I am missing?

Correct in the situation of a single loudspeaker (headphone) into one amplifier output. Very high impedance headphones were developed for and have a "better" attribute when plugged into console of parallel connectors from one amplifier and your goal is to just "monitor" the audio without affecting the power delivered to the more critical main loudspeakers. Not the detectorists' application at all.

Jasong you are correct in your assessments of loudness v impedance matching and frequency response of amplifiers v the loudspeaker (headphone). http://www.soundonsound.com/sos/jan03/articles/impedanceworkshop.asp This link is way more than a detectorist may need to know, however this article (for musicians and studio people) is well written and accurate.

GPZ7000

I have been very very pleased with my GPZ 7000. I don't use it in trashy environments and I love its ability to see deep stuff and small stuff and wiry gold in quartz in one machine with one coil. Now that I'm used to the controls and audio it absolutely is my go to detector. I've got several hundred hours on it now and I have absolutely zero regrets about the purchase. Is it perfect? No, and neither is my iPhone 5s. I am not plagued by early catastrophic failures or twisting shafts. (Maybe cause there is so much grit on mine the shaft doesn't twist. Stop cleaning it! :-) ) There are a few user interface things that make me go "huh?", however all are very workable once you're used to it like so many other modern devices. It's heavy and the harness is not practical where I hunt. I don't share the views of others who are unsatisfied with general ruggedness. I am sure I am as hard on mine as the vast majority of users and mine is used every week 2-4 days. Some ferrous discrimination in the future would be awesome. It was fairly advertised as an all metal detector. New timings for heavily mineralized environments people are having trouble in (me included a small minority of my time) would be a big win for the future. I can understand this could be very frustrating if it was the majority of your hunting . To the point of Minelab not listening to the customers, they came out with the ferrite ring and ground balance procedure a few months after release on this issue. Admittedly I've only been doing electronic prospecting for a year, the last 9 months very intensely. Therefore I don't have a long history on many predecessor VLF and PI detectors. (I own three other detectors and have used two others belonging to colleagues.) I have been designing military, industrial and consumer wireless electronics for 30+ years and I am quite impressed with the Zed overall. I'm a very satisfied customer. It is "worth $10K" to me and my budget. I find it completely reasonable that someone else in their environment, their existing investment in detectors and their budget might not think it is worth $10K to them. It's justifiable business that Minelab would price it at $10K and see how that goes - basic economics supply and demand.

Steve, quick note to publicly acknowledge I like these policies. I come to this forum for relevant detector prospecting info. I like how you keep it to just that. Saves me a lot of time to not have to navigate through irrelevant stuff.

As much fun as a series of successful fishing trips AND pays the expenses much better. Congrats Chris.

Good advice here. The Bounce sheets are a new one to me. Convenient to pack, I'll remember that one. I'm chiming in mainly to confirm my past positive experience with soap application as a preventative. Also apply to body under your clothing "protected" areas since the nasty oils do get through fabrics when you're as heavily immersed as you describe. Consider getting your Dr. to give you 1) the steroid prescription in pill form to take with you to the bush and/or 2) prescription steroid cream. Obviously not something to take routinely, however, if you're breaking out like crazy miles from nowhere ...

I finally got around to upgrading to Pro. Steve, thanks for researching & posting the license key. Tvanho, Here are a couple quotes from WIkipedia entry on Google Earth. https://en.wikipedia.org/wiki/Google_Earth ... "It maps the Earth by the superimposition of images obtained from satellite imagery, aerial photography and geographic information system (GIS) 3D globe. " ... "For other parts of the surface of the Earth, 3D images of terrain and buildings are available. Google Earth uses digital elevation model(DEM) data collected by NASA's Shuttle Radar Topography Mission (SRTM).[12] This means one can view almost the entire earth in threedimensions. Since November 2006, the 3D views of many mountains, including Mount Everest, have been improved by the use of supplementary DEM data to fill the gaps in SRTM coverage.[13]"

I am starting a thread on GPZ discrimination. In this missive I use “discrimination” with reference to both hot rock and junk identification. Let me start with my hypothesis then describe how I got there. I am very much asking for corroborating or contradictory evidence to my hypothesis and other notes as well as any other useful info on GPZ 7000 discrimination. Hypothesis: Natural gold from small, barely perceptible signal return, to huge enough to provide overload, always produces a high-to-low tone when in high yield gold mode / general ground type settings. Natural Gold can sound either high-to-low or low-to-high in difficult or severe ground type settings. Ground type is the only user changeable setting that effects tone changes high-to-low or low-to-high on a particular target. Required Conditions: negligible EMI, negligible other metal or overriding hot rock present. The one thing that has been true to date in my field experience and experiments, is that every natural gold find or test nugget from small, barely perceptible to huge enough to provide overload, had a high-to-low tone when in high yield/general. I understand this hypothesis is no giant breakthrough enabling classification of the Zed as anything other than an all-metal machine as the Minelab manual and advertising clearly classify it. Nonetheless, it’s the entire useful conclusion I’ve come to in as few words I can make it. (I have trouble with writing few words. J ) Minelab makes no mention of discriminating sounds yet the pitch change of high-to-low or low-to-high is impossible to ignore, and naturally causes the curious to explore.* Early in my experimentation and Zed education, I spent hours determining what controls affected a reliable pitch change in different junk materials and hot rocks and gold. All kinds of elaborate charts in my notebook. I am glad I have not posted on this topic earlier because I have been through many cycles where experiments and field experiences would give me some preliminary beliefs which would soon thereafter be disproved by another experiment or field experience. What has emboldened me to make this post (as simple as the hypothesis is) is that I was fortunate recently to experiment on a very large gold in quartz specimen. Not certain on the mass of gold (> several ozs for sure) yet the return signal easily produces overload response on all gold type/ground type combinations. (No, not my gold. L ) The specimen produced high-to-low on high yield/general, low-to-high for difficult and severe ground types. Always true as I backed the Zed coil away from the specimen. This was enlightening and counter to my early Zed experimentation on aluminum where size of aluminum changed pitch direction. I found that the Zed, with no change in settings, will respond high-to-low on small pieces of aluminum foil (several mm x several mm) yet respond low-to-high on large (>100 mm x >100 mm) keeping high yield/general constant as well as all other settings. Zed responds low-to-high on soda and beer cans with high yield/general. So, I have wandered about assuming the same for gold (size of metal can affect pitch change) and hence I have NO DISCRIMINATION at all. I “convinced” myself of this when I tested a 1 gram nugget (high-to-low) then a very large men’s gold wedding band (low-to-high) keeping high yield/general constant as well as all other settings. Hence my hypothesis states “natural gold” to distinguish from alloys. Hot rocks, iron or mineral based, produce a symphonic range of return sounds and can be high-to-low or low-to-high on any ground type or gold mode setting. (another thread necessary on hot rock strategies.) My hypothesis of “Ground type is the only user changeable setting that effects tone changes high-to-low or low-to-high on a particular target.” is not in conflict with the fact that you can put audio smoothing on high and totally eliminate a return from a weak target. Audio smoothing setting does not change the pitch direction on a target. Iron. Man made iron and high % iron alloy objects produce low-to-high on all ground types only if the iron is not rusted heavily. If the iron is rusted it can produce high-to-low or low-to-high. This of course is near useless info for the prospector because most all iron stuff we find is rusted. Since I work in a hard rock environment, "dig it all" is just not practical. Hence, my experiments and documentation on the GPZ7000 tones to try and get any possible discrimination info out of it. In my environment, that mostly means hot rock. In my environment, I can prospect in high yield/general at least 90% of the time. Mineralization puts me in difficult or severe less than 10% of the time. I also have the “luxury” to mark interesting signal location first located by GPZ, then come back with my Whites MXT to try and discriminate. (Also have GMT, GB II and GB Pro available.) This works well on strong signals, or near-surface hot rock, however weaker GPZ signals produce inadequate response for any accurate discrimination from the VLFs. Even if your environment requires you to mostly search in difficult or severe ground type settings, you could always go high yield/general as a discrimination test right over the target. Of course then you might have "overriding hot rock" condition. I think the most opportunity for uselessness of my hypothesis, even if it's accurate, is that I just don't have much experience of gold in difficult or sever ground environments whereas that is much the norm elsewhere. * My previous Minelab experience is just ~ 80 hours with a GP3000, so I come to GPZ 7000 without much Minelab audio discrimination experience. I’m told on other posts in this forum that is a Zed education advantage.