best coil for big gold deep

hi all, just thinking about getting a big coil for my 5000 and was thinking does any one use big monos or is the18" DD the go what works best in mild to hot ground and witch has the best alround proformance, I normally run the 14" NF coil (biggest I have) and want to chase big nuggets deep! what are your thoughts????

Hey Joe
I have a 20" NF Mono you can borrow to try out mate!!! the usual cut will apply

Seriously mate it is here for as long as you want it!!!

What?    you have given up on finding small gold?      now your gonna try and break her in on the big deep stuff eh?    you go girl!!!   you go!!!....   I will be right there with you digging that bad boy out .............partner

Wayne,

What do you consider big mate?
And what is deep to you?

For me big is 5 oz + and deep is 700mm or deeper and I would run a 25in nugget finder mono on my 5000.
DD's are only better in very mineralized ground, which is VERY rare up your way.
So its likely you'll never need to use one unless you want to discriminate.
The 25in is a specialist coil for large deep gold and is not sensitive to small gold.
As such I would not use it in general situations as you will mis heaps of smaller gold.

that might be a plan lee,better throw it in for next weekend if the rain holds off like I think it might!!! I was thinking DD only for the black soill out here where the monos are unusable an old mate was telling me about a place where big monos whould not hush so the 18DD it was only to produce a 14oz and 11oz piece (where we tried to go last weekend) that's why im interested to try one out, yeah wayne I suck at small so im gunna try to hit her hard that sweet talk don't do her much good so it is time for bad joe!!! whould be nice to try that coil lee just for shist and giggles!!! talk soon cheers joe,

joe82 wrote:that might be a plan lee,better throw it in for next weekend if the rain holds off like I think it might!!! I was thinking DD only for the black soill out here where the monos are unusable an old mate was telling me about a place where big monos whould not hush so the 18DD it was only to produce a 14oz and 11oz piece (where we tried to go last weekend) that's why im interested to try one out, yeah wayne I suck at small so im gunna try to hit her hard that sweet talk don't do her much good so it is time for bad joe!!! whould be nice to try that coil lee just for shist and giggles!!! talk soon cheers joe,

Is the black soil from the break down of metabasalt?
I've done well in black soil areas up your way, but they are not what I would call noisy ground and you should be trying to use a mono as a dd's depth is less than half that of the same sized mono, so even if you have to use a smooth class timing and lower the gain you will still get way better depth with a mono.
I've found what you FNQ boys consider noisy ground is not really that noisy, as the wet season rains leach most of the minerals from the soil and your so called noisy areas are only noisy compared to the average ground up your way which is quiet and I normally run normal timing no probs most of the time.
So if I was you I would borrow Lee's 20in and find a setting combo that works, the 20 still has OK sensitivity on gold as small as 2g, you will find much smaller but only right on the winding.

Aurumpro wrote:

joe82 wrote:that might be a plan lee,better throw it in for next weekend if the rain holds off like I think it might!!! I was thinking DD only for the black soill out here where the monos are unusable an old mate was telling me about a place where big monos whould not hush so the 18DD it was only to produce a 14oz and 11oz piece (where we tried to go last weekend) that's why im interested to try one out, yeah wayne I suck at small so im gunna try to hit her hard that sweet talk don't do her much good so it is time for bad joe!!! whould be nice to try that coil lee just for shist and giggles!!! talk soon cheers joe,

Is the black soil from the break down of metabasalt?
I've done well in black soil areas up your way, but they are not what I would call noisy ground and you should be trying  to use a mono as a dd's depth is less than half that of the same sized mono, so even if you have to use a smooth class timing and lower the gain you will still get way better depth with a mono.
I've found what you FNQ boys consider noisy ground is not really that noisy, as the wet season rains leach most of the minerals from the soil and your so called noisy areas are only noisy compared to the average ground up your way which is quiet and I normally run normal timing no probs most of the time.
So if I was you I would borrow Lee's 20in and find a setting combo that works, the 20 still has OK sensitivity on gold as small as 2g, you will find much smaller but only right on the winding.

Well Aurumpro
Mate you have just confirmed what I have thinking for a while now!! the ground ain't that HOT, sure there are pockets that get very noisy, but in my limited experience & yes I still run an SD2200 with a 14"NF mono coil mostly I am able to have it running quite smooth & quiet, to the surprise of many GPX users, granted I dig many ground noises but they can turn into a signal occasionally.

rc62burke wrote:

Aurumpro wrote:

joe82 wrote:that might be a plan lee,better throw it in for next weekend if the rain holds off like I think it might!!! I was thinking DD only for the black soill out here where the monos are unusable an old mate was telling me about a place where big monos whould not hush so the 18DD it was only to produce a 14oz and 11oz piece (where we tried to go last weekend) that's why im interested to try one out, yeah wayne I suck at small so im gunna try to hit her hard that sweet talk don't do her much good so it is time for bad joe!!! whould be nice to try that coil lee just for shist and giggles!!! talk soon cheers joe,

Is the black soil from the break down of metabasalt?
I've done well in black soil areas up your way, but they are not what I would call noisy ground and you should be trying  to use a mono as a dd's depth is less than half that of the same sized mono, so even if you have to use a smooth class timing and lower the gain you will still get way better depth with a mono.
I've found what you FNQ boys consider noisy ground is not really that noisy, as the wet season rains leach most of the minerals from the soil and your so called noisy areas are only noisy compared to the average ground up your way which is quiet and I normally run normal timing no probs most of the time.
So if I was you I would borrow Lee's 20in and find a setting combo that works, the 20 still has OK sensitivity on gold as small as 2g, you will find much smaller but only right on the winding.

Well Aurumpro
Mate you have just confirmed what I have thinking for a while now!!  the ground ain't that HOT, sure there are pockets that get very noisy, but in my limited experience & yes I still run an SD2200 with a 14"NF mono coil mostly I am able to have it running quite smooth & quiet, to the surprise of many GPX users, granted I dig many ground noises but they can turn into a signal occasionally.

Yes mate if you can still ground balance its not noisy ground, a lot of hobbyist guys and even some pro's don't really know the difference between emi and ground signal and on the modern gpx machines they walk around in fine gold timing and compare it to older detectors and say that their gpx is noisy but it is not, its because fine gold timing is more open on the fast time constance side so it let's through more emi and in some ground that will make the detector appear more noisy but if you go to normal this fast time consance noise is now gone and you have got way more depth on long time constance targets even you have to turn the gain down to deal with the ground signal.

yeah mate that whould be the plan try the 20" in normal and work out gain and stuff as I go, not to sure on the black soil (is it all broken down basalt?) im still getting my head around all that stuff I will just have to play around and find the best timing that runs the quitest and deepest I have a area where the 4000 and 14" round have found a couple of 2gm bits tried the sdc and got 42 bits of bird shot!!!! nothing with the 5000 yet so big coil time

Joe. I have all the big coils if you want to try them. Dick.

Aurumpro wrote:

rc62burke wrote:

Aurumpro wrote:

joe82 wrote:that might be a plan lee,better throw it in for next weekend if the rain holds off like I think it might!!! I was thinking DD only for the black soill out here where the monos are unusable an old mate was telling me about a place where big monos whould not hush so the 18DD it was only to produce a 14oz and 11oz piece (where we tried to go last weekend) that's why im interested to try one out, yeah wayne I suck at small so im gunna try to hit her hard that sweet talk don't do her much good so it is time for bad joe!!! whould be nice to try that coil lee just for shist and giggles!!! talk soon cheers joe,

Is the black soil from the break down of metabasalt?
I've done well in black soil areas up your way, but they are not what I would call noisy ground and you should be trying  to use a mono as a dd's depth is less than half that of the same sized mono, so even if you have to use a smooth class timing and lower the gain you will still get way better depth with a mono.
I've found what you FNQ boys consider noisy ground is not really that noisy, as the wet season rains leach most of the minerals from the soil and your so called noisy areas are only noisy compared to the average ground up your way which is quiet and I normally run normal timing no probs most of the time.
So if I was you I would borrow Lee's 20in and find a setting combo that works, the 20 still has OK sensitivity on gold as small as 2g, you will find much smaller but only right on the winding.

Well Aurumpro
Mate you have just confirmed what I have thinking for a while now!!  the ground ain't that HOT, sure there are pockets that get very noisy, but in my limited experience & yes I still run an SD2200 with a 14"NF mono coil mostly I am able to have it running quite smooth & quiet, to the surprise of many GPX users, granted I dig many ground noises but they can turn into a signal occasionally.

Yes mate if you can still ground balance its not noisy ground, a lot of hobbyist guys and even some pro's don't really know the difference between emi and ground signal and on the modern gpx machines they walk around in fine gold timing and compare it to older detectors and say that their gpx is noisy but it is not, its because fine gold timing is more open on the fast time constance side so it let's through more emi and in some ground that will make the detector appear more noisy but if you go to normal this fast time consance noise is now gone and you have got way more depth on long time constance targets even you have to turn the gain down to deal with the ground signal.

Hey Aurumpro

Mate thanks for the explanation!!!! , it is the stuff like this that I copy & paste into a word DOC to save it for when I get a GPX, even though I don't have a GPX yet I am getting an understanding of them from what guy's like put up on forums!!!
Cheers and please keep it coming, "Golden Year" to you man!!!!

joe82 wrote:yeah mate that whould be the plan try the 20" in normal and work out gain and stuff as I go, not to sure on the black soil (is it all broken down basalt?) im still getting my head around all that stuff I will just have to play around and find the best timing that runs the quitest and deepest I have a area where the 4000 and 14" round have found a couple of 2gm bits tried the sdc and got 42 bits of bird shot!!!! nothing with the 5000 yet so big coil time

Broken down basalt is a red brown color and you will normally find basalt hot rocks everywhere, metabasalt is completely different to basalt as its origin is from the plate edges / oceanic trenches and has undergone metamorphosis and its a very old rock.
Where as basalt is lava flow and is usually much younger and has not undergone metamorphosis.

yeah this has no redish coulor just black grey looking stuff but it meets a red wash tells me it may be a fault line (correct me if im wrong) also its on top of a ridge that drops slowly away down to a creek, there are deperisions on top where the black soil is laying in pockets, I have found gold further down this same ridge so I was thinking the big coil the top around these patches of black soil,i have had the 4000 there and had to run in sens smooth because of the noise that's why I thought about a big DD to tame the noise???? hey tricky how are ya? mate might have to take ya up on that offer next time ya out, let me no and I might be able to catch up! cheers joe.

Mate I'd definetly be trying out  the biggest coil's u can ,specially with the bit of moisture around in the ground ,presume your in Nth QLD  I'm here at Croydon ,and it staggers me at how much having some moisture in the ground makes a difference ,etc  going over old ground that I was in  Normal  from several months ago where I ran into some spots of hot rocks ,ground noise ,going over the same area now in Normal again  and virtually no ground noise at all ,getting to wave the coil virtually under the bottom wire of a fence ,where as months ago coundn't get within metre of it ! HARDLY having to ground balance !!!! virtually no EMI ,except from pops from the thunderstorms as only to be expected of course ,the 18/12 coil I'd highly recommend ,works for me !! TOTALLY agree with what Aurumpro wrote ,I made those mistakes when I first got the 5000 ,having only had a 3500 before .IT takes a lot nowadays to shift me out of NORMAL ,THOU admittedly in my situation being a hard rock area ,still use Special / fine as I'm predominatly chasing specimens ! Got to admit too that this the first I've ever detected over the WET ,even my 2 VLF'S are loving it !!

joe82 wrote:yeah this has no redish coulor just black grey looking stuff but it meets a red wash tells me it may be a fault line (correct me if im wrong) also its  on top of a ridge that drops slowly away down to a creek, there are deperisions on top where the black soil is laying in pockets, I have found gold further down this same ridge so I was thinking the big coil the top around these patches of black soil,i have had the 4000 there and had to run in sens smooth because of the noise that's why I thought about a big DD to tame the noise???? hey tricky how are ya? mate might have to take ya up on that offer next time ya out, let me no and I might be able to catch up! cheers joe.

Mate if you've only ran the 4k over it you should find heaps as the enhance and fine gold timing are way better than sens smooth in all but the worst long time constant type soil, both in depth and sensitivity.

hugh62 wrote:Mate I'd definetly be trying out  the biggest coil's u can ,specially with the bit of moisture around in the ground ,presume your in Nth QLD  I'm here at Croydon ,and it staggers me at how much having some moisture in the ground makes a difference ,etc  going over old ground that I was in  Normal  from several months ago where I ran into some spots of hot rocks ,ground noise ,going over the same area now in Normal again  and virtually no ground noise at all ,getting to wave the coil virtually under the bottom wire of a fence ,where as months ago coundn't get within metre of it ! HARDLY having to ground balance !!!! virtually no EMI ,except from pops from the thunderstorms as only to be expected of course ,the 18/12 coil I'd highly recommend ,works for me !! TOTALLY agree with what Aurumpro wrote ,I made those mistakes when I first got the 5000 ,having only had a 3500 before .IT takes a lot nowadays to shift me out of NORMAL ,THOU admittedly in my situation being a hard rock area ,still use Special / fine as I'm predominatly chasing specimens ! Got to admit too that this the first I've ever detected over the WET ,even my 2 VLF'S are loving it !!

Hi mate
I too have expirenced the same thing many times in regards to the moisture in the soil.
I have found nuggets at fernominal depths for their size after rain in areas that I had done over previously.

well there ya go! I never new about that I just thought that with rain comes the leaching out of minerals making the ground noisy? so it makes everything quiet and has the reverse affect??? and with the rain around I should be working areas that ive done before???

Joe 82 ,mate whilst I don't retract anything I wrote yesterday ,I do how ever think there must be a cut off  point ,before the ground must get OVER SATURATED  ! I remember watching JP explaining SALT /mode / timings on the 5000 ,but that I think that was shot back in 2010-2011 when we had that huge wet !! So I'm asking my self ,just how much more moisture can this ground take before it doe's start to do the reverse ??? It's also raised the question of my previous comfort zones as to what I've been used to ?? timing's ,audio etc

ture that mate, the more I think about it some days do my head in!!!

You also have ground that gets way noisyer some to the point of being un detectable.
This is usually iron rich clayey ground.

And then you have ground that is not evenly wet (like strait after rain) so this makes it noisy, this affect is also worse in clay.
But go to the same spot 1 or2 days later when the moisture has evened out and hey presto ya got the extra depth, up your way there are also a lot of areas that have penetrateing ground, ground that has the right conductive property to carry the detector signal to fernominal depths and this is even more pronounced when the soil is evenly moist.

cheers mate, that whould explain why the area I was in today was a little noisy. it rained last night (mabie 15mm) and its red clay ground,couldent use normal at all had to run fine gold and even then a little murmur now and then. I will have to check it out in a day or 2 just to see the difference!!!!