First Gold Nugget With MDT 8000

[Steve Herschbach]

I explained on another thread that I was interested in giving the MDT 8000 a spin looking for gold nuggets in trashy locations. All mining camps are places where supplies were hauled in, and none of it left the site, but is scattered everywhere. Miners were not into wasting time, and if possible built their shack, or cabin, or small town, right in the middle of where they were mining. It is not uncommon therefore that there is good gold right in and around some of the trashiest locations in old mining camps. Time has passed and often the wood is gone, rotted away, or left behind when the structures burned to the ground. Old nails and remnants of rusted cans are the most common items, but every manner of metal item that might be needed to survive and mine in the wilderness might be found.

There are detectors that might do better on the tiniest gold nuggets than the Tarsacci MDT 18000, but the MDT has a hot 18 kHz mode that is more than sufficient for common VLF nugget hunting tasks. I knew without even trying it that the MDT 8000 would have the sensitivity I was looking for. My main question was whether it offered anything I could not live without for finding gold nuggets in locations littered with ferrous trash. It is also very common in mining areas that the ground is quite mineralized, though that is not something that is universal.

I gave the MDT a go at a location where there used to be a shack built on some gold bearing ground out in the Nevada desert. The shack is gone, but there are plenty of cans, remnants of cans, nails, door hinges, bed springs, stove parts, etc. All the metal stuff that was ever brought there, but was not valuable enough to be scavenged as the years passed.

The bottom line is the MDT 8000 did not disappoint, and I did manage to find a gold nugget in the limited amount of time I had. The nugget is interesting to me in that after cleaning it weighs exactly 1 gram, as weighed on my very accurate digital powder scales. I find a lot of nuggets that weigh about a gram, but I don't really recall ever finding one that was 100% spot on before. It's probably happened and I did not take notice of it, but this time I did.

Gold nugget fresh out of the ground

Exactly 1.00 gram!

The good news is I did not find anything particularly difficult about using the MDT 8000 on this short test run. I bounced back and forth between mixed mode and disc mode a bit, and far preferred mixed mode. I am big on audio information, usually running detectors in full tones and preferring modulated audio. I also prefer having visual target id information available, I'll take all the tools I can get, but in general I hunt by ear and prefer complex audio. Many people would find the way I run my detectors to be too noisy or busy but with nearly 50 years of detecting under my belt my detectors talk to me and I want to hear everything they have to say.

So mostly mixed mode, black sand and salinity off, sensitivity to max, and ground balance manual 668 on this ground.

This is admittedly a very preliminary report based on limited use. However, It does not take me long to come to general conclusions about metal detectors. The Tarsacci MDT 8000 is more than capable for the task of VLF nugget detecting, with gold sensitivity as good or better than popular prospecting models running in the 18 - 20 kHz range. While the machine is very capable, there are a couple things that left me shrugging my shoulders a little bit. First, the audio. The tones chosen for revealing non-ferrous targets are extremely high, with the high tone being almost out of my discernible frequency range. Imagine a "tink" sound like tapping a glass bottle with a knife handle. I have some definite high frequency hearing loss, and while the MDT is usable for me, I'd be lying if I said I loved the audio. There are no tone adjustments I am aware of on the MDT, so it falls into the realm of something I just have to live with. There is some ability to modify the response by perhaps trying different headphones looking for those that deliver the tones as they are in the best fashion possible, but that's about it.

The other thing is that many discriminating detectors have a common enemy, the flat remnants of steel cans. Think steel cans,  thin wall wood stoves, thin steel roofing... bits and pieces of flat steel anything. Coin and jewelry hunters are quite familiar with the challenges presented by bottle caps. If anything the problem is worse in old mining camps due to the volume and variety of this type of trash item. And unfortunately the MDT 8000 is as prone to calling these ferrous targets non-ferrous as are multitudes of other detectors. That's not a knock on the MDT, but it's a bit of magic that if present would make it or any machine stand out in these types of situations.

Some problem items, and a small brass item

One of the first non-ferrous targets I found with the MDT 8000 is some kind of very small brass.... something. A little pin-like object. I was impressed by this find before I found the gold nugget, and it alone told me the MDT had the hots needed for the job. I can only speculate how the MDT would do with a small coil... no doubt extremely well on very small targets. For now however the coil that comes with the MDT 8000 is the only one available, and since this machine is aimed at the beach market, all the push from other people seems to be for a larger coil. I'd be surprised therefore if a smaller coil is ever made for the machine. The existing coil is very good, though for nugget detecting it would benefit from a solid bottom scuff cover/skid plate, to make it less prone to hanging up on sticks or sharp edged rocks.

What about the target id on the gold nugget? I have to admit I was paying no attention to target id at all so do not know. I was just listening for any medium and high non-ferrous tones and digging those.

To sum up, I am not here to promote the Tarsacci MDT 8000 as a gold nugget detector and am not saying anyone should go out and get one just for that purpose. I would say however that if anyone has this detector, it is as capable, if not more so, of performing the task as many detectors made specifically for gold nugget prospecting. I plan on giving the detector another and more lengthy workout at another location in the future, though it may be a few weeks before I report back. In the meantime, for anyone with an interest, I recommend watching this video below by Keith Southern. Pay particular attention to the sounds the detectors makes to get an idea of what I mentioned above as regards the tones. And let's close with one more look at that first gold nugget with the Tarsacci MDT 8000. 

One gram gold nugget found by Steve at trashy site using Tarsacci MDT 8000

 

[Dances With Doves]

Nice hunt .One day you may  bump into a gold coin in spots like those.I don't think to many people  can claim a gold coin and  a nugget in the same day.

[Aaron]

Very nice report Steve! Hope to see you using the Salinity balance next time. The salinity could have calmed that tin down for you. Didn’t you get a couple coil covers w that unit?

[Steve Herschbach]

16 hours ago, Aaron said:

Very nice report Steve! Hope to see you using the Salinity balance next time. The salinity could have calmed that tin down for you. Didn’t you get a couple coil covers w that unit?

Yes, the unit came with two fitted scuff covers. But not a solid full bottom one like I am describing would be beneficial as a nugget hunting accessory.

I wish the salinity control was a magic solution. However, even run at 50 it has no discernible effect on these type flat steel targets, while at the same time definitely attenuating the response to gold nuggets. That is why I ended up running it disabled.

[Carolina]

I have owned my first Tarsacci over a year and a half now and have tried no less than five different sets of phones on it. I liked it so much I bought a second one used. I also prefer mixed mode as it is ( for me ) deeper than all metal or disc. I too have a rough time with the high tone but for me, after much testing, the Sun Ray Pro gold are by far the phones of my choice. I am a water hunter mostly and I don’t worry about them not being waterproof. With the control box submerged mostly, I rely on tones only. I especially like the volume controls to balance out the audio. Don’t let the simplicity of the machine fool you as there really is a multitude of settings available in combinations that at first you may not pick up on. All in all, it is a fantastic machine. Congratulations on the nugget. First time out that ain’t bad !!!

[kac]

Can you hear the iron off the edge of the coil? I do that quite a bit to check on bottle caps when coin shooting. Get bit of a grunt on edge tip or tail and I move on.

[Steve Herschbach]

1 hour ago, kac said:

Can you hear the iron off the edge of the coil? I do that quite a bit to check on bottle caps when coin shooting. Get bit of a grunt on edge tip or tail and I move on.

Nugget detecting in mineralized ground can be a bit tricky. The bottom line is pretty simple... gold reads well into the ferrous range. This means that if you employ any ferrous discrimination at all, you will leave some nuggets behind. This is why serious nugget hunters always dig all targets, and why an $8000 nugget detector like a GPZ 7000 has no ferrous rejection.

But some places have too much trash and you do not have enough time. You can go about the situation in a couple different ways. You can aggressively try and make targets go ferrous, and in highly mineralized ground, if you try hard enough, you will probably succeed. You will also walk away from more gold than a person who is willing to dig targets that are “iffy”, which is the other way to go about it. Do you look for reasons to dig, or look for reasons not to dig? It is not uncommon at all to get targets that give off both ferrous and non-ferrous responses, bouncing up and down. They could be trash, they could be a nugget. Do you dig them, or don’t you?

All I can tell you is these flat “tin” targets read aggressively non-ferrous. This is not like some unknown issue... many detectorists can tell you about the wonders of rotted steel cans. The only detectors that I know of that pretty much squash the stuff are the BBS/FBS machines, but they are also not well regarded as nugget machines by many people for various reasons. One major reason being that the aggressive rejection of ferrous comes at too high a cost in gold nugget capability.

Non-Ferrous Reading As Ferrous

Tune Out Nails, You Will Miss Gold

Ferrous/non-ferrous overlap region