Minelab Eureka gold tips, settings, questions

[Chrisco75]

Great to see you having some success Bob!!
You are obviously tuned into the Eureka's language.

I would be very interested to see how you go carefully gridding the raked area and the mullock heaps the gold is coming from with the WOT coil in 6.4khz to see what, if any, has been missed with the PI and also to see the Eureka's capability on the larger gold.

I bought one the other week and gave it a swing a couple of weekends ago and was very impressed at how it handled the hot ground around Waanyarra.

It speaks a very different language to the other frequencies and coils though so will take a bit of getting used to!

I did not find any gold but only had the coil on the ground for about 6 hours so can hardly expect to find anything in such a short time.

It handles hot ground very very well though. Looking forward to checking it on quiet ground around Rheola.

Keep us posted

Chris

 

[bob]

Just an update on the specimen finds from 22nd May. I put the specimens in Ali Brite for a day but they showed little change. Day two the visible gold looked brighter but the other rock was unchanged. This was not what I expected. By day three there appeared to be no change. I lost patience and fished them out and washed them thoroughly. The acid had softened the rock somewhat and I used the pliers to crush away the stone. The gold structures were very delicate and broke easily just picking them up. The brown iron stone like material was interesting. It was like a conglomerate containing small grains of quartz, some larger bits of quartz that had small specks of gold, plus inclusions of gold cemented together by a brown glue. Most interesting. The separated gold weighed in at 1 gram. I did manage to recover some sizeable bits that are very prickly and still have small grains of quartz attached.

Maybe I will try leaving them longer if I find some more. Having never done the acid treatment before I did not know what to expect.

cheers Bob.

 

[Chrisco75]

Hydrochloride does the job to eat away ya softer stone.
After that put them in some mag wheel cleaner to brighten up the gold.

 

[bob]

Thank you for the information Chris. Hopefully I'll find some more specimens to experiment with. On 29th of May I went on another visit to Mystery Reef. It was not as busy as the previous two visits so I took some pictures to add to my previous posts.

It may not be very clear but this is an old detector hole. Walk three metres to the left and that was where I found my first specimen.

Walking three metres to the right around the other side of the mullock and this is the magic spot that produced seventeen specimens and four bits in total for three visits.

This shows the raked area which is visible and exists below the magic mullock heap. I checked this out a bit last week. (29th May) and believe that it might pose a challenge as the area has been burnt. The burning was done some two years ago I believe and there is a lot of charcoal around all amongst the stones. For other detectors this may not be a problem, I do not know but the Eureka is very sensitive to charcoal under certain circumstances in particular wet ground. It sounds very much like a target. I will give the area a go though as the next picture will show that my magic mullock heap is done giving up treasure I think.

These were my finds for 29th May. Three clean bits weighing 0.015g, 0.019g and 0.032g. They were all very tiny and not much more than a blip on the threshold even when in the scoop.They were all found on the magic mullock heap. This mullock heap is a typical spot where the Eureka will work well. The grey material is very quiet and non reactive. Once the odd hot rock was removed any blip could be examined for a potential target. Finally the magic mullock is silent and I think that it is time to explore some other parts of Mystery Reef and the area below.

Cheers Bob.

 

[bob]

My detecting Journal entry for 27th July.
"Today I spent the afternoon at Mystery Reef. After eight weeks away it was good to walk on 'wild' ground, find some quiet space and not be surrounded by a crowd of people. My plan was to split my time between the standard coil (10x5), the 6" gold seeker and the 11" round. I started with the 10x5" at the mullock heap that has produced all the specimens. It took a while to get used to the detectors noises and setting up the threshold. It didn't feel right at first. After about an hour I began to develop a smooth sweep action which helped maintain a steadier threshold. Then I got a soft signal; not gold but a small brass pin or tack. I was encouraged to continued searching even though I had done this heap a number of times. My next target was a signal just like the previous one. Scraping gave a stronger signal and after two more scrapes the target was unmoved. I was really excited by this stage. I continued scraping until the target moved. Once recovered in the scoop I had a small rough looking rock that gave a positive signal. A rub between the fingers confirmed that I had a small specimen with the familiar band of brown material wedged between some lighter grey rock.
I gave the 11" coil a go all over the mullock heap but no big specimens only one big nail/spike about 10cm long and some lumps of rust found at depth obviously out of range of the 10x5". The 6" gold seeker turned up nothing but I did learn to control it a bit better by being more careful to stay at a slow sweep speed and not vary the height above the ground. It is a really sensitive coil. A great start back."

(The specimen weighed 0.177 grams intact. Didn't bother with a photo, it looks just like a small rock. Will soak it. Did I say Mystery Reef was done? I'm going back with a rake on Monday.)

Cheers Bob.

 

[bob]

Two posts in one day?? Just catching up.
Monday 31st July.
' Today I returned to 'Mystery' Reef armed with a rake. The first thing to do was smooth off the 'magic' mullock heap and repair the area that I had pulled down with my pick. I then scanned the area for targets. Nothing but I really felt out of practise after a lengthy time away. I then started to rake into the heap pushing some material aside then detecting the exposed soil. After an hour or more I got a signal that turned out to be a sliver of brown rock. Some spit and a rub revealed a hint of gold. This find gave me the motivation to continue raking material aside and detecting. Another hour or so produced a second specimen and a third turned up when I decided to check the dirt that I had piled up with the rake. Below is a picture of my excavation works.

More raking and detecting turned up another signal. This time I thought that I would check the target in other frequencies. The signal disappeared in 20kHz and 6.4kHz so I determined that it was a small shallow target. I was surprised at how far I had to dig to recover the target. The hole with scoop is shown below.

The ground was loosely packed large stones and I think that the target was sinking while I was digging. Eventually I recovered the specimen pictured in the scoop. If you look closely there is a thin band of darker rock which is typical of the specimens that I have found in this area.

The brown layer was only about 2mm thick so I was not expecting too much but four specimens was a fair result for the afternoon. The specimen that weighed 0.177g found last Thursday cleaned up to weigh 0.103 grams. Added to the gold recovered from Monday totalled 0.303 grams.

Did I say that 'Mystery' Reef was done, maybe just one more look???

P.S. I did fill in and repair the mullock heap before I left.

Cheers Bob.

 

[AU Fever]

I love your perseverance Bob! Great to see you're still pulling gold out of that heap

Cheers,

AU Fever

 

[bob]

Hi Au
Now that I have been lucky enough to find a bit at one spot, I am struggling to let go. When do you say you're finished with a spot and move on? Two afternoons at 'Mystery' Reef produced nothing but rubbish. It wasn't a waste of time though as I needed to re-acquaint myself with some hotter ground which is the norm rather than the quiet mullock heap that has produced all the results. Each time that I went back I still gave the heap a bit of a scrape to see if I could snag another piece hidden a bit deeper. On Wednesday 9th August I intended to spend my first full day out since starting back but I made a monumental stuff up. When I arrived at the reef and started to set up I realised that I only had one battery. The other was still at home on the charger switched on. It had already been on over night. With no-one home I decided to return, turn off the charger and collect the battery. So a planned whole day shrunk to a half day. I decided to use the rake and dig back the north side of the mullock heap a bit like the photo above as I had found two shallow clean pieces on an earlier visit. My efforts were rewarded with one more small clean piece (0.049g.) and two small specimens that crushed up for 0.151g. Renewed gold fever took over and I was back there on Friday (11th August). Another stuff up, I forgot the rake. Raking back the heap with the pick was really hard but it did produce two small specimens. One I thought was a piece of shot but while scratching at it with a finger nail, it broke in half to reveal a bit of gold showing in both bits. Having some gold in the jar I went to look at other heaps around the reef. This was good because I found some fresh holes unfilled. Someone else has an interest in the reef. As well as refilling the holes I managed to locate some pieces of shot near the holes which is a good sign that my detector was set up well. At about 4 o'clock I returned to "the mullock" heap to have a cup of tea and repair some of the dragging down that I had done earlier in the day. With the job done I still had forty five minutes up my sleeve. I gave the mullock heap another sweep over the repaired area but nothing was evident. I decided to work from the top of the heap by standing on the top as the sides were a bit crumbly. Well a slight blip turned into a target, then another and another. I snagged a clean piece and three small specimens. On two other occasions I lost a target. While smoothing out the dig pile to locate the target I sent some marble size bits scuttling to the base of the mullock heap. No target in the dig pile. I'll look for them next time. Below is the crushed results from Friday. Total weight 0.309 grams.

So the total for the last two visits 0.509 grams. Some of the targets have been found by digging down because they were initially out of range of the detector, but detecting these specimens is very tricky because the signal is dependent on how they are placed in the ground. The specimen pictured in my last post is very typical of what I have been finding. Orientated the way that it is in the scoop, the specimen will give a very strong signal. However on its edge, rotating it around the signal varies from very strong to almost no existent. The gold even though small is clustered in a thin layer in the specimen, so it's a bit like detecting a coin. Laying flat the signal is strong but on its side the signal is weak. So just disturbing the ground a bit has turned up targets as well. The next visit hopefully I will remember all the necessary equipment but I will have to give the top of the mullock heap a bit of a scratch as well as searching the other heaps.

Cheers Bob.

 

[roy cobb]

Thanks for the update Bob great read and lets us all know how the Eureka works well
Roy

 

[AU Fever]

Thanks again for the update Bob :Y:

You are one with the Eureka...

 

[VLFr]

Bob. Just love reading this Eureka Blog. I have a Eureka Gold set up with only 1 coil a 6 inch coiltek. Been using this combo for about 6 months now. Found everything but gold with it, though I don't think its far away now. We did find a mini sunbaker sitting next to a massive hole after it rained. Dom :Y:

 

[bob]

Thanks again for the update Bob thumbsup
You are one with the Eureka...

Obi-Wan has taught me well but I still may be tempted to move to the dark side (SDC 2300).

Hi Dom
Welcome to the forum. I am pleased that you enjoy reading this thread. The stuff that I post here comes straight from my prospecting journal. I do a write up when I get home and generally read the last two entries before going out again, so that I have a plan for my day detecting. Also it is meant to ensure that I take all the necessary equipment but that hasn't been happening lately. An interesting set up that you have with your Eureka. I though the 10x5" was standard and you had to buy the 6"gold seeker as an extra. My first 6" was faulty but still found gold. The one I have at the moment is better but requires careful attention to the sweep movement to stop it squealing and making other weird noises but the ground is very hot in places and changes quickly. Plenty of hot rocks! The 10x5" has become my go to coil at the moment. Good luck with your search. If you have read all of this thread then you will know that it took me a while to experience success but perseverance has won out in the end. So stick with it and enjoy being out in the bush.

Cheers Bob.

 

[bob]

Cold and wet so time to catch up on this thread!!!
Wednesday 16th of August.
Today I started at the now famous mullock heap at 'Mystery' Reef. I searched from the top to the base in an area about a metre wide looking for the two targets that I pushed over the edge last week. No luck there. They could be jammed between larger rocks and if they were orientated on their sides they would be very difficult to detect. I then began digging and raking into the top as illustrated below.

I picked up a flat clean piece after about the third dig and rake. This was the breakthrough that I needed to convince me that what I was doing was worthwhile. The depth also gave me a clue as to how much material I should remove each time. Then another clean piece and a small specimen turned up. Needless to say I continued. Conditions were hard as it was extremely windy, the soil was wet and a bit noisy compared to other times. After four hours I took a break at about 2 o'clock. The traditional tea dunking ceremony was performed showing two almost clean pieces with fragments attached and a small specimen showing a bit of gold. Returning to work netted my fourth target another small specimen. The idea of removing dirt to the depth of my last target meant that I was working more efficiently and so far I had found nothing in the pile of raked back dirt. Today I had the presence of mind to switch frequencies on each target. The two small clean pieces did not register on 20kHz or 6.4kHz. The two specimens however did register a signal on 20khz. I was surprised at the size of the small specimens given their target response. Rain sent me scurrying back to the car for an enforced twenty minute break. Resuming produced another specimen that gave a good signal in both 20kHz and 60kHz. It was a bit bigger this time. All the specimens were located at a depth of between one and a half to two inches and would have to be laying on their flat sides to be detected at this depth. Continuing to dig, rake and detect produced another signal. An exciting one because it responded to all three frequencies though in 6.4kHz it would pass for ground noise. Before I could dig the target rain intervened and I had to leave my scoop marking the spot. Within ten minutes or so I was back on the heap really excited about this dig. With the target out I located the target under a flat piece of stone I thought. I picked up the stone in my left hand and a scoop of dirt with my right. No target in the scoop. I dumped the dirt from the scoop and dropped the rock in. Yahoo my biggest specimen yet!!! Another shower of rain developed steady this time. I was tempted to just pack up and go home but if I was to come across the mess that I had made I would not be happy. So I donned a rain coat and restored the heap as best I could to the way it was at the start of the day. I left a couple of bigger rocks to mark the depth that I had worked to, incase I decide to go back and continue benching into the heap. I have benched into the base on the North and West sides with some success but it was much harder repairing my work as the material had to be shovelled back. Yesterday storing the material as I did and working form the top made it easier to rake the material and repair my mess.

The finds from 16th August. The three smaller specimens and almost clean bits (0.060grams each)

The big specimen. The tooth picks mark two spots where gold was showing. I think that once I scrubbed it up at home with a toothbrush it was showing in about four spots. How exciting!!!!

The crushing was carefully done last night in front of the television. The two bits either side of the match were the first pieces for the day and went 0.060 and 0.063 grams. Most of the chunkier bits came from the smaller specimens. The big specimen contained clusters of small bits around 0.02g in four concentrated spots. If it was laying in the ground flat side up as in the photo that would explain the good signal response. The big specimen produced 0.349g, the smalls 0.308 and the clean bits resulted in a total of 0.780g for the day. Can't wait for it to stop raining and get back out there.

Cheers Bob.

 

[Roscoe]

Beautiful specimens Bod and thanks for your detailed pictures and explanations, you deserve every piece you get.

 

[AU Fever]

Wow Bob, that's awesome work.

Loving your blog :Y:

 

[bob]

Another chapter in the 'Mystery' Reef saga.
Tuesday 22nd August
Today I found out that 'benching' a pile is hard work. Gloves would have been good and leaving my pick at the back door was definitely not a good idea. Scraping possible targets with the plastic scoop worked okay but the side of the pick gives a nice smooth surface and getting the coil down flat on the ground is important in picking up these small specimens.
Despite forgetting stuff again the day started well. Each time I have returned to the pile, I have detected over the disturbed or repaired ground. I do this because usually at the end of each day when I rake back the pile and repair my digging I pack up and go home. The practise of going over the disturbed ground has netted me the odd early target. This morning was no different. Ten minutes in I had a small specimen virtually on the surface. I thought that I may find more in the dirt that I benched out last week. So I slowly raked back and detected the dirt that I did last week. No more targets. I started around ten o'clock and did not pick up any more targets until I started to get into new ground around one to one thirty. I got a really good signal in all frequencies. I could have really used the pick. A nice blob of rust came to light. Raking and detecting produced five very small specimens that were just flat rock chips, nothing much really. The early morning was difficult as the soil was quite wet on top but things improved as I benched into drier ground. Not sure whether I will continue benching. It's almost time to look elsewhere but there's that old saying gnawing at me, "Its a mistake to leave gold to find gold." There's a small area left un-dug and the pile next to this one has produced a specimen at its base. It needs to be thoroughly checked before moving on. So maybe this reef will get one more visit.

The crushing of the specimens was surprising given their small size. Some bigger bits (two) went 0.078g and a couple 0.05g. A lot of the smaller bits weighed 0.02g. All up the lot including dust weighed 0.404grams. Better than finding nothing. For the next trip I need to remember to take all the necessary equipment, bench out the last 30 centimetres of untouched ground and do a final tidy up? If nothing significant turns up I guess it will be time to move on.

Cheers Bob.

 

[Roscoe]

Bob. One or the members on this forum by the name of loamer, was setting up the
Detector in one location and passed the stone over the coil. I think this technique
Would suit your current location and may speed things up for you?

 

[AU Fever]

Hi bob, good work as usual.

I used to keep a checklist on my phone of stuff to take out detecting. Before I left home I'd have a quick glance at it to make sure I hadn't forgotten anything.

 

[bob]

Hi Roscoe and Au
I read your posts Friday morning and I'm sorry I took off detecting. When I got home it was a quick shower and out. So there was no time to reply. The check list idea on the phone is a good one. My problem has not been remembering things but one of getting distracted during the load up phase. On the trips out to the car with stuff I have gone off to do something else then taken off without things. I may have been suffering from a bit of gold fever or over enthusiasm as well, given my recent finds. I was focused on Friday and managed to remember everything that I needed. It was good that I read your post Roscoe as I was able to look at the heap and asses whether having the detector fixed and just pass dirt over it with the scoop would be as effective. At 2 metres high, 3 metres wide and 4 metres long that's 24 cubic metres of dirt or forty eight trailer loads. That would take a long time to sort a scoop at a time. Some of the targets that I have found in the last two sessions could easily be missed in a scoop full of dirt, particularly if they were on the top. After dislodging the small targets, the only way that I found them was detecting in two directions to pinpoint and then gathering the smallest amount of dirt in the scoop. This put the target in the bottom of the scoop and made it audible on the pass over the detector. Working a small area with the detector has been really good for my skill development. One reason that I am missing targets is I think that I do not always overlap my sweeps. I think that I move forward with the detector too far at times. Anyway thank you for your replies. I did have an okay day out Friday but that is another story. Maybe I will get that done in the next day or so?

Cheers Bob.

 

[Roscoe]

No Bob, That's not what i meant. What you have to do is if the gold is associated with a particular stone in the piles, just pass that type of stone over coil. In your case it seems to be associated with these red stained rocks or rocks with red banding through it? and leave the rest.