Your thoughts on the smaller DD coils please.

[JohnApthorp]

My setup at the moment consist of an 8inch mono on the Infinium.
I have found this setup grossly inadequate for finding small gold.IE: anything less than 1 gram that is buried less than 1 inch. It has no problem detecting a .22 bullet at 4 inches but any deeper - forget it.

I recently tested it at a test patch that was set up last year. No hope of finding a .22 bullet shell at 6 inches. It did find a large fishing sinker at 7 inches though.
Things improved slightly when I used a booster with it. You could hear the fishing sinker slightly louder. No other change in the other signals.

When I fired up the AT Gold, it had no problem detecting a .22 bullet at 4 inches. The bullet shell at 6 inches was just detectable & the fishing sinker at 7 inches was no problem what so ever.

My question is: Would the 10 x 3 inch DD coil make a difference?

The factory 14 x 10 inch coil that comes standard, was sold soon after I picked this unit up because it was just as useless as the 8 inch mono.
Maybe I'm expecting too much out of the Infinium?
It was purchased new from an authorised dealer about 2 yrs ago.
Maybe I got a dud?

I would greatly appreciate other peoples thoughts on this detector.
What would be a reasonable size target to expect at the 4 inch mark. Surely it can detect targets smaller than a .22 bullet at 4 inches???

Thanks,

Gary...

 

[John-Edmonton]

Any chance of teaming up with someone who also has an Infinium. That 8" coil should do much better then the depths you are describing to me. That concerns me. It should be very sensitive to the .22. The only way to not pick up the .2 would be to switch on the iron check, which I am sure you don't have engaged when you hunt. And of course you have to swing the coil slow to get the deep targets.

Good luck! I hope you can get it performing better then it is.

 

[Mega]

@John-Edmonton,just received a new 8inch Mono coil in your reply to the opening post you mention about swinging the coil slow,would you consider a normal swing speed as slow or would you reduce the swing speed down even slower ??? Can you expand on that one please.It does make sense so that the detector has time to work out the feint deeper signals.

 

[John-Edmonton]

2 feet/2 seconds is what I recommend. Even slower if you are in trashy areas or are looking to find those extreme deep targets. Make sure you set your threshold at 4-5 for maximum depth and your discrimination at 0-1.

 

[sws33]

There has got to be something wrong with the coil or the unit itself. I'm am constantly amazed at the tiny things I find at the beach and at great depths with the 8" mono. I had been using the 5" x 10" DD for quite awhile as the weight is so light I can swing the detector all day. It was having some issues so I switched to the 8" mono and now the beach I hunt seems like a new place.My Infinium will pull fishing swivels at 8" easy. I even found the broken ear piece from a pair of sunglasses with that tiny hinge being the only metal on it and pulled it out of 5" and had no doubt about the signal.

 

[OLD FART]

I think the best coil is the 8 inch mono. That is what I used on mine all the time. The small dd coils really won't pick up much smaller gold but are much nice to work in tight areas that the 8 inch mono won't go. Make sure you are ground balanced properly, 0 disc and threshold set high as to blow your ears out. If you run barely audible threshold you will lose a lot of depth and also run in lock position after you get it ground balanced. The infinium will not pick up small gold like a vlf. It will not go as deep onsmall gold as a minelab 5000. I also used a 14 inch mono on mine but went back to the 8 inch because it seemed to perform better. Hope this helps. I had mine for 8 years and just could not get it to find small gold very well. I could find a 50 cal bullet at a foot deep though too bad it wasn't gold.

 

[Mr. SIG]

If the infinium won't pick up small gold with the smaller DD coil is it worth it to buy. Haven't purchased yet, but I thought it could do both small and large gold nuggets.
Please advise.

 

[James02]

Small is relative. I use a GB2 as my primary machine, most gold in my area is small. There are times the ground is too hot, ergo the Infinium. I've found the Infinium will find relatively fine gold, using 8" mono. If I find gold of decent size with GB2 I always followup with Infinium. This has been a good technique for me, I've found some larger deeper nuggets I missed with the VLF.

 

[Dave Malton]

Which coil would be best for prospecting nuggest and small gold in the Arizona Desert?

Thanks for any info

 

[Fishers Ghost]

The 8 inch mono works very well and can handle most ground iron mineral conditions. The 10 x 14 mono or DD give better coverage and will respond to the same small gold that the 8 inch mono and small DDs will respond to. Pinpointing small nuggs (Sub Gram) is difficult with the large coils. A pinpointer is handy when using these coils.
The small DDs lack depth on large nuggs but are great for sniping along bedrock cracks for small gold and getting in around the rocky areas.
These coils require a very slow sweep speed of approx one foot per 3 seconds as apposed to the one to one and a half feet per sec for the other coils.
The 5 x 10 will find small gold but is a bit quiet and for some reason or another it does not get the depth that the 8 inch mono can achieve on larger nuggs of 5g and up.
To get the best chance of finding small (sub Gram) gold with the 10 x 14 mono and DD the sweep must overlap by 1/3rd of the coil per sweep. Three sweeps to cover the length of the coil.

 

[James02]

Very good information. Many folks do not use the correct speed and wonder why they Don't find smaller nuggets.

 

[Mega]

@Fishers Ghost,that makes alot of sense the swing speed,i use the 8'' and 14x10'' Mono over here in the UK and i have to admit i still prefer the smaller coil out of the 2 for every day use,it maybe not as deep but depth is not everything the coil seems more responsive on smaller targets as well,better pinpointing and also much lighter.

The larger Mono coil is nice to have just incase you need the extra depth and will mainly be used on 2 hoard sites that we are working on at the moment,one is a Celtic goldstator site and the other is a Roman Silver Denari site and just on these 2 sites the larger coil will earn it keep and also the detector as well.What the magnitude of these sites are like we are still not sure as its a scattered hoard but as yet we have not found the containers of these coins,hence the need for a Pulse machine.

Is the 8''Mono coil the most popular choice for this detector and if so is it for the reason that i have mentioned,over here in the UK most of the finds are within the top 8inches anyway so the smaller coil should hit most of the targets,my way of thinking is,if you do have a good clean productive site then use the smaller coil 1st and then when the targets dry up use the larger Mono coil to go down to the next productive layer.

Swing speed has been one of the major things that i have been working on this last 18 months or so,although my swing was never fast infact much slower than normal but since reducing it down ever further and also reducing my forward motion at the same time my finds rater has doubled i would have thought.Its funny just by doing these 2 small things can have a amazing results and they are free,you dont need a upgrade to a better detector just reduce you swing and forward motion speeed that is all it takes.

HH from the UK

 

[James02]

Your comments on swing speed are right on. When I started using my Infinium I was going crazy because I was not finding gold I was sure was there. My VLF detector tolerates a relatively fast swing speed. Once I slowed down I started finding more. In open areas I use the big DD coil, but most of the time I use the smaller DD coil except when around water, I use the 8" mono.

 

[Fishers Ghost]

@Fishers Ghost,that makes alot of sense the swing speed,i use the 8'' and 14x10'' Mono over here in the UK and i have to admit i still prefer the smaller coil out of the 2 for every day use,it maybe not as deep but depth is not everything the coil seems more responsive on smaller targets as well,better pinpointing and also much lighter.

The larger Mono coil is nice to have just in case you need the extra depth and will mainly be used on 2 hoard sites that we are working on at the moment,one is a Celtic goldstator site and the other is a Roman Silver Denari site and just on these 2 sites the larger coil will earn it keep and also the detector as well.What the magnitude of these sites are like we are still not sure as its a scattered hoard but as yet we have not found the containers of these coins,hence the need for a Pulse machine.

Is the 8''Mono coil the most popular choice for this detector and if so is it for the reason that i have mentioned,over here in the UK most of the finds are within the top 8inches anyway so the smaller coil should hit most of the targets,my way of thinking is,if you do have a good clean productive site then use the smaller coil 1st and then when the targets dry up use the larger Mono coil to go down to the next productive layer.

Swing speed has been one of the major things that i have been working on this last 18 months or so,although my swing was never fast in fact much slower than normal but since reducing it down ever further and also reducing my forward motion at the same time my finds rater has doubled i would have thought.Its funny just by doing these 2 small things can have a amazing results and they are free,you don't need a upgrade to a better detector just reduce you swing and forward motion speed that is all it takes.

HH from the UK

Mega B.

I find the sensitivity of the big mono to be excellent and near enough matches the 8 inch on coin size targets for depth as well..
The 10 x 14 comes into its own in open ground where you think there may be some deep targets (below 14 inches). Generally this coil can achieve greater depth on larger than most average coin size items than what the 8 inch mono will get. In heavy trash areas the big coils will likely drive you bonkers and then the small DD may be usefull but detection depth of these coils is not all that flash. plus you will have to reduce the sweep speed to around half the ideal sweep speed of the Large coils. The large coils like a sweep of around 1 to 1.5 Fps Sec. If your targets are around coin size and up and are within approx 10 inches of the surface you can pick up the pace a bit with these coils
I would use the big mono in open ground in pref to the 8 inch mono but be sure to overlap each sweep by at least 50 % of the coil..

If you are expecting to find gold or sil chains the infinium will not respond to very light weight chains with small or very thin links. On the other hand I would imagine that the chains that were made in ancient times were not small and sissy like some gold chains today.

Large metal boxes (Up to a foot square) will be detected deep with either of the 8 or 10 x 14 coils inc the DD 10 x 14.possibly to better than three feet but in this case the tone may only be a wavering change in the threshold and not a Hi/Lo or lo/Hi. The detector will not respond to the gold or sil contents enclosed in an shut All Metal box. it will respond to the box only.

Even some cigarette tin size items can be detected to approx three foot with the Infinium and the 10 x 14 coils.

Remember that the Rev Disc can give you a clue as to whether your target may be gold.

The signal from gold will always be Hi/LO in rev Disc at a reduced strength than the signal in Normal mode. Weak signals from gold will often be discriminated out in Rev Disc.
Small gold items give a HI/Lo tone in Normal And a reduced strength Hi/LO in Rev Disc .
Large gold items will mainly give an LO/HI tone in Normal but will be HI/LO in Rev Disc.

The simple rule for the Infinium when gold hunting is to Always recover targets that produce a HI/Lo signal in Rev Disc and in particular those signals that are HI/Lo and at a lower strength to their signal in The Normal mode..
Iron can sound like gold but gold will not sound like iron. So the worst case scenario is that if you use the Rev Disc Iron discriminator correctly you may occasionally dig up some iron but you will not leave any gold in the ground.

The result may not always be gold but by doing this you will not leave any gold in the ground.

A lot of silver can give a LO/HI or HI/LO tone in Normal mode and a similar strength Lo/Hi or HI/LO in Rev Disc.....Unfortunately silver often sounds like an iron response.

The Rev Disc on the Infinium is designed primarily to separate gold from iron, which it does quite well and to the depth of the target.

 

[Mega]

@Fishers Ghost,many thanks for taking the time to explain the indepth qualities of each of the coils,it has been very helpfull,i only have a narrow window every year to get back onto this site mainly due to the crops being harvested and ploughed and rolled for the next crop.This is the main reason that we have to have a like military style time frame to cover the small are and be as thorough as we can each time we are allowed on.

The coins from the hoards are in a tight radius and what is called a scattered hoard ie when the tractors get bigger and more powerfull they drag the plough deeper and drag a few more coins towards the surface,have been speaking to a few other people who have found similar haords and they average depth appears to be about 20 inches i guess this would be the arm length of someone laying on the ground and depositing the container in the hole.

I have to admit i have learn alot from your replies and will put them to use when we visit the site again i hope within the month.

Once again many thanks for your help.

 

[Fishers Ghost]

24 inches will be pushing the Infinium to the limit with the 10 x 14 mono on large single coins of 25 to 30 mm diam..
The response I have mentioned re the Infinium and gold is for high purity gold in the 18 to 24 kt range. Other gold alloys can produce a wide range of different responses.

Detectors like the Sov XS and other Explorer Series detectors fitted with the WOT coil are great relic and jewelery detectors. The Sov has been known to give an iron tone on gold in highly mineralised ground.
The old XLT Spectrum in the All metal mode can achieve good depth in mild ground when fitted with the standard 9.5 inch concentric. I will not part with my XLT in a hurry.

 

[Mega]

@Fishers Ghost,just to clarify the actual pot,container of coins would be at 20inches not single coins,the coins could be any depth from on the surface down to the level of the container so going by your experiance the larger 14x10 Mono should be able to locate the hoard and then the digging begins.

 

[Fishers Ghost]

Yes the 10 x 14 mono should fine.
If the pot is metal it will respond to the pot, not the coins inside (If the pot is sealed). if it is broken open then the coins will/may add to the signal.

The detector will see a jumble of coins as not much more than if they were just one coin because of the poor conductivity between each coin.
So if the pot is ceramic and is full of coin, the signal may not be a big as you might imagine.

A high qual vlf may signal stronger on a jar of coin than the PI. So it would be a good idea to have a vlf on the go following the PI as well. (Just in case)

The PI generates separate eddy currents in each coin, not one big field in all of the coins. If the coins are in good electrical contact with each other the PI may signal stronger. But do not be expecting a massive signal.
A single coin within a 12 inches of the surface may signal stronger than a horde of coins at 20 inches.