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Is Depth All That Matters?

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So everything I say is in regard to Salt Water hunting. For me, Depth with Functionality is important. 

As a younger buck, digging everything was not an issue. Now, digging everything is an impossibility. 

Personally:  Depth, with the ability to pass over some junk, and STABILITY in moving Salt Water are my goals. I like running my detector on the edge where it is a little sassy. I need a detector that will do 7 inches min on a decent size chunk in moving salt water.  Otherwise it does not matter how "nice" the detector is. 

Oh ya, and GOLD, lots of GOLD!!!!    

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In most of the parks and public areas where I hunt, the really old coins are 8" or deeper down to around 12" So, any VLF detector that can hit coins that deep AND give me a good idea what they are = low, mid or high conductor is a detector I will use a lot. Any other detector that cannot do that will sit in the corner or get sold. I don't mind just going out and hunting for shallow coins and recent jewelry drops. It can get old however and going for deeper jewelry and older coins is really a challenge. In most places where I hunt there is next to nothing past 14" unless there was a garbage dump there or the ground has been extensively disturbed. There just hasn't been enough habitation here by humans using metal to worry about deeper targets.

When I am fresh or salt water beach hunting I just want good ferrous/non ferrous discrimination and 10" of good ID. In the surf I only have time for a couple of scoops so depth is not a big deal.

When I am gold prospecting with a VLF I want great hot/cold rock/ferrous/non ferrous discrimination for shallower, smaller gold targets down to about 8". With a PI I am happy with normal coil sized depth for the larger gold and the ability to ignore ground noise.

So raw depth is rarely an issue for me. VLF target ID accuracy, non ferrous target unmasking, target separation and ground mineralization handling are much more important. A PI for me needs to be as lightweight and portable as possible yet also be able to take a good beating, hit small gold in bad mineralization and still go fairly deep on larger stuff.

Great topic,


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A terrific and very interesting topic,but one that although the common denominator here is 'metal detecting' can vary and we adapt using what detectors best suits the job in hand ie in Aussieland or Arizona and your targets are gold nugget hunting then depth is important as well as a machine for extremely small targets hence high freq VLF and PI suits that type of detecting.

For me personally and for my type of detecting and the targets that i am after here in the UK then i use machine best suited to our extreme historical past going back 1000s of years,also the extreme variations is materials used,this could be from using gold,silver,bronze,lead and many other different metals and also the added twist and complications of additional metals into various combinations eg a silver coin or gold coin from say 1000 years ago could have a higher content or even a lesser content of base metal due to how the economy was at that time.

So for me i tend to use 2-3 or even more detectors as in my mind no one detector does it all across such a wide spectrum as what we have on offer,so my way of thinking is that i use 2 main machines ie Deus and Equinox that cover the freq from 4khz upto 80khz then also bring into the equation also not desirable targets like some extremely trash roman/saxon sites then also coil size on the 2 main machines also can improve the odds in your favour,so matching coils to said machines can also be as important as using the correct freq.

For the most part even though our history is extremely rich and varied most common finds across the spectrum are found within the top say 6-8'' for the most part,hence most detectors can find these common finds like say roman and silver/gold hammered coins using a stock 10'' coil,but also its not uncommon for us to find finds that are say the highly valuable ones this could be say artifacts or hoards which could well be below the eveyday 8'' finds layer that most folks like detecting for.But by using a everyday detector most folks unless its a very large pot could possibly miss these more desirable deeper hidden targets like hoard.One has to remember that banks and other saving institutions are modern forms of saving valuables but with such a long history as on the UK the safest place to store valuables till war and other major problems past was by hiding said artefacts and valuables in the ground near say a strategic location near a tree,building or what ever waiting for the original owner to return and retrieve the item but alas this often never happened hence the reason why so many hoards are found and this is my personal opinion many many more are still awaiting to be found.

This brings me onto my obsession with either using VLF or PI machines with larger coils like my TDI Pro,2 Nexus machines and also my TW-5 twin box and the reason for this is that if i suspect that even the slimmest of possibilities that a large artefact/hoard could be in that location due to the previous history then i always carry one heavy hitter with me as well as my 2-3 machines that i use,the logic behind my way of thinking is that if i find say a tight radius of coins this is a classic indication that a scattered haord that has been clipped by the plough is in this area then the heavy hitter either VLF or PI comes into its own and yes i have used these a few times.I like to think that i try and cover all possibilities if i am away on a days detecting and these means from small single coins right upto large deep artefacts and hoards and also increase the odds in my favour.It may seem like i am over doing it but if i was using say just one machine with a happy medium stock coil then i would find possibly everything upto say 12'' depending on item size that is but targets that are more desirable maybe deeper upto the average hoard depth of say a man laying on the ground and putting said hoard at arms length from say 18-24'' depth and in some cases deeper.

Its possibly a long winded post and possibly folks who hunt solely for deep gold would not relate to how i detect and why i use the detectors that i do and the methods that i use,but i can only mention how i detector and why,but sharing this fascination and interesting hobby of ours is always wonderful.

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A million dollar's question here🤓...

In my modest experience on the saltwater field I feel comfortable with an old Ctx when there's no more than 25 cm of sand to cover the "ground zero"...No matter the coil size, this is the max depth where I can trust what the screen try to say and my ears can tell if a thin interference can begin a signal if I dig a bit more...Increase the coil size and You gain coverage+noise/lose signals quality/lose stability...Reduce the coil size and you gain sensitivity/keep acceptable depth/lose coverage...

From 30cm of sand above the "ground zero" and my eyes are blind without evidence of prime ground, then the PI can do for me...(maybe)..

Considering that more sand usually means more light stuff including aluminum of all sort and sometimes deep...A PI still can drive you crazy...Definitely I pray for erosion, I wait and I follow storms or the most similar phenomenon to be called like that...

Vlf still win 2 to 1 against a PI....If you have to keep high the grams/time ratio...

For this reason high expectations for an efficient/discriminating/ deep/ PI are so true but....Who knows when.....

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Target ID accuracy for me really depends where I am digging. If I am relic hunting or in the woods all I need is the 2 tone mode (ferous+vco) and an approximate # to give me an idea what it might be. I base my depth needs to the clay line. This can vary from just a few inches to 16-20" in old meadows. Average depth for majority of the places I hit are under 12" and more often in the 6-10 range so all of my detectors handle that well. I have learned that with all the iron in my parts that larger coils can be counter productive. I have only found 2 silver dimes at the 14" mark in some swampy edge of fields with a 17x15 coil. Larger coils don't necessarily gain much more depth here in many areas due to the iron as they tend to get smothered and masking becomes more of an issue. The weight of larger coils can really take the fun out of hunt as the day wears on.

For the salt, I prefer my pi for the simplicity and lack of chatter. I may try my MK out there later this season when things cool down and crowds subside but not sure how well it handles the black sand patches and hot rocks we got.

I actually like my pi with the 8" coil in freshwater because it swings so easy though it doesn't see small ear rings.

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9 hours ago, Jeff McClendon said:

In most of the parks and public areas where I hunt, the really old coins are 8" or deeper down to around 12" So, any VLF detector that can hit coins that deep AND give me a good idea what they are = low, mid or high conductor is a detector I will use a lot.

I can't say much about searching for natural gold since, living where I do, I haven't had much chance to do that with a metal detector.  And water/beach hunting isn't my thing.  Old coin hunting is my area of concentration.

Jeff mentions 8-12 inch depth in his area.  Simon gets another several inches in his cointopia site.  My ground doesn't seem to hold coins at those kinds of depths.  I don't remember getting any coin deeper than 8 inches.  Having said that, I've only found one 90% silver coin (Washington 25c) and only a couple > 95% copper coins (USA 1864 2c and 1917 Canadian 1c) larger than dime/penny.  Even nickels which the Minelab Equinox multifrequency really likes, I still haven't found below 8 inches.  So is it my technique or detector that's limiting me?  I don't think either, and here is some (admittedly sparse) evidence.

My recorded coin hunting time accumlation has reached 1000 hours.  The two oldest coins I've found are an 1867 Shield Nickel (Fisher F75) and an 1864 2 cent piece (Eqx 800 as chronicled here).  Although the ground hasn't been kind to either, the details show that both these coins were in circulation for a very short time.  I.e. if not for the ground damage they would grade Very Fine or higher.  The nickel was found near a 19th Century homestead.  I don't know when that homestead was established, though.  The coin was no more than 6 inches deep. 

The 2 cent piece history is a bit better captured, I think.  Although I found it in a park established ~1920, I was since told that there had been a (pre-deployment) Civil War Union troop camp there.  At the time I found it I was scratching my head as to how it got there.  Now I at least have a good theory.  That coin was only 5 inches deep, even after 'living' there for >150 years (if my CW camp theory is correct).

So to get back to Steve's question, simply more depth likely won't help me, at least in my parks and schools.  Better separation (unmasking) from both aluminum and iron trash would help, a lot.  The Eqx 800 multifrequency has plenty good enough TID for me.  It also has the best separation abilities of any of my detectors.  But I want more, and I need more if I'm going to find more coins in these trashy (and likely previously hunted) sites.

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