Black sand pyrite sulfides and gold

[im1badpup1]

I just wanted to post pictures how tiny the gold is what the goldcube has captured.

Cant wait for my classifier set to come its the only way il get it out the concentrate properley and theres plenty in the concentrate

The brown looking stuff is gold for somereason my picture quality resolution isnt as good when uploaded onto the forum

Ive panned this twice already but im a learner panner

 

[cosmetal]

Good looking . . . you're on your way to being a true panner!

Couple of pointers:

Make sure you pan into a water tub to catch any "escapees".

The bottom of your pan looks too smooth and is still shines. Take some very fine wet/dry sandpaper and scrub the bottom portion only. This is called "seasoning" your pan and it does help when going after very fine gold.

Definitely classify your cons and pan the last two of your screens to see where your gold is showing the most.

You said before that you do not run into a lot of magnetics. But, if you ever do, take a neodymium magnet from a HDD, put it into a heavy plastic bag and remove your magnetics before panning. Save the magnetics as you may have trapped some fine gold.

Have you viewed all of the videos at https://goldcube.net/gold-cube-university/ yet? The one titled "Fine Gold Recovery Challenge" is long but does have a lot of good pointers.

Let us know the results from your assays. :?:

James

 

[im1badpup1]

Thanks the video link n tips have sure helped me out.

Ive been out today testing a couple of different locations. Im hoping to find a good accessable one.
Ive took some pics of the kind of locations im testing. Sounds hard to believe but every pan i did had yellow in it!
The sand is brown it looks actually very much like the concentrate from the gold cube. In fact almost identical.
Sample 1 undercliff
I got most here 1st pan about 14 2nd pan over 25. 2nd pan id scraped the clay bed more.

Sample 2 clay bed gulley
I got 2 bits 1st pan and over a dozen with the 2nd having dug deeper into the crevice

Amongst rocks
2 the 1st pan both was the largest 2 flakes of the day. 2nd pan 9 smaller. Again id scraped the bed better with 2nd pan.
I did a couple of pans in each weather was atrocious wind blowing the water clean out the pan! How i managed to get any result is a feat in itself.

Its a much better concentration level than my previous location with this test by far. Several times better.

Exposed clay bed of beach. Theres channels and crevices full of heavy material and patches of concentrates scattered about.

Unfortunately its a similar problem of a working time of only 6hours or so here.

I know of a couple of other locations with huge heavy sand deposits of the same type as the ones ive been currently testing where accessability is good and can work 24/7 only the highest tides will cover. Unfortunately theres several feet of overburden on them presently but as the season changes they will become exposed. I think they will be the best concentrarion of gold in them too. Because theyre made up of repeated blacksand concentrate deposition and only partial erosion before another deposition on top. Several depositions all in one.

Im thinking of how best could a high volume sluice be made to suit the conditions and gold type material im after recovering? Im wondering if i can combine working a dredge sluice when the waters high and use the pump to operate a manual shovel fed sluice when tide goes out. I mean use the same sluice and pump with both ways. And whats the pumping range- limits of a dredge pipe?

 

[im1badpup1]

I tested cube tailings and im losing gold. Im sure a partial reason is the large amount of lead and lead like heavy metal ore. Theres gold down the cube in the matting not where expected and the lead heavy stuff is engulfing the best catchment area.

I thought about this as a solution. Using a magnetised bed what my material slides into hopefully trapping the heavy lead. The rest of the lighter material flows or rolls over the magnetite/iron filing magnetised bed.
The flow rate for a magnetised sluice ive seen is the same as the cube.
Then i thought if i can play it smart enough and use the correct strength magnets and shapes i can manipulate the geometry of the bed and create a concentric geometric pattern with varying density levels of filings.
So throughout the bed theres pockets of low resistance material can fall into as it flows.
If i get the magnet size and strength reasonably close the system should be forgiving in that magnetics will build up and clear at a certain point without actually clogging the system and density and gravity favouring gold as well as lead i should trap both well size been not a bad thing

So at the worst i trap the lead and keep my cube clean.

i cant find any good information yet on magnets best size and shape. Quadrapolar positioning of rectangular magnets leaves a square hole or theres ring magnets of varying hole width. There wont be any actual hole though its more a moving fluid carpet of iron filings or oxides etc with high and low density pockets of resistance.
Il buy some n42 and n50 neodynium magnets in a few days but id welcome any information what helps determining size strength and shape to get in the meantime. Enough for a 12x12inch tray.

Ive one pattern in mind whats called halbach array. The link shows a 2 dimensional pattern of flux field. Stacked side by side itd create the low density pockets https://en.m.wikipedia.org/wiki/Halbach_array the magnets here are cubes in line and can be added to indefinately
. The next line slightly offset and so on.
Id probably sink the cubes in plasticine and put a plastic sheet over to test. It means the sluice bed is level and its easy to swop and change configurations and manipulate magnetic field strength

 

[im1badpup1]

Ive got a nice sieve set so im able to size my blacksand concentrate from 10 to 100 mesh 10 20 30 and so on.
Its made an amazing difference to panning the concentrate out well. At 30 to 50 mesh i found 1 or 2 pieces per pan id missed. At 60 about a dozen.
80mesh and my concentrates come alive with gold particles, 50+. Im finishing off the 90 and 100 later today. Im hopeful for 'invisible' gold in the smallest mesh pan.
Theres some really heavy material in the last spoonful of the pans i was wondering if i was to oxidise and then reduce to a small pig bar would an xrf give me a good enough reading to determine whats in the bar?
It doesnt have to be particulaly accurate in % of the elements contained just knowing whats there will do. And what collector metal would be most compatible for xrf reading?

Its just i can get an xrf reading done same day for a tenner i dont have spare cash for fire assay yet.

Il post a couple close up pics of the concentrate ive panned from the concentrate later. The concentrate ratio is high when i worked out my blacksand is already very concentrate to begin with eg no blondesands then im getting 2-3litres per ton max. Have sized and concentrated by panning that to just several ounces in total.

 

[cuchugold]

Forget the XRF. Do a torch assay. Same as a fire assay but less accurate. Your gold reading will be within 1/1000. You only need access to an accurate balance, not even your own. Do the fusion melt, and place the lead button in a cupel, then aim a torch with an oxidizing flame about 5 mm above the lead button, and wait for it to cupel. Use added silver in a ratio of 2.5-2.75 to the amount of gold. Then part the silvery button in nitric acid, and weigh it. Total cost is about $5.00.

Re. magnet use: The proper way to use a strong magnet is above the black sands, not under the pan. Copper, silver, and gold are moderately repelled by a strong magnet (diamagnetic), while magnetite and others are attracted.

Also, impure gold in extremely fine particles will look brownish or black, and get mixed up with the black sands.

 

[g_axelsson]

Do you have an UV-light lamp? (Black light) If you do, use it and watch if there is any fluorescence in that heavy sand concentrate.
Zircon and scheelite often shows up in the black sand concentrate. I have had pans that looked like a starlight sky when I tried it. Zircon is bright orange and scheelite from bluish white to yellowish depending on amount of molybdenum in it (scheelite - powellite series).

I don't know if you will be helped by knowing if there is a lot of zircon or scheelite in your concentrate, but it never hurts to know. Maybe you could use it as a trace mineral of where the gold hides out in the field.

Göran

 

[im1badpup1]

At 100 mesh the strangest sights while panning..
It looked like liquid metal at one point after id panned so much off. Thats all the magnetite and hematite completley removed at this point. They was lighter than this material. It wasnt actually liquid metal. Just tiny particles flowing.

Then that layer have way to this sediment a strange bright shiny metal sat with the lead amd gold . I found an amalgamated ball of mercury what had picked up most the gold.


Im wondering if any of the brown/black particles are similar to what you mention cuchu?
I was under the impression about the magnets it depends on the impurities in the gold to how itl react to magnetism. I was going to add a riffle set or trap with magnets to try stop some of the lead entering and filling my goldcube prematurely. Then a mat after the cube with areas of low-no magnetism hopefully heavies will fall into and settle. But use magnetite or iron filings to create the mat. Ive got a mineral what if i drop on the magnet it bounces away. Orange one.

I noticed a few zircons in my sediments goran il try a uv and see what reacts itl be interesting to see. I think it may help if i was somewhere else looking primarily for platinum group metals the geology where im thinking of is much different and concentrated areas arnt so easily defined by visible black sand. But garnets and zircon and similar gather in patches. Id bet its a good place to start looking and uv would help spot them.

The mercury contamination was my fault. Id opened a container with mercury inside over my pan at one point to put material in. Some was caught in the screwcap and fell out into my pan and sediment.
Its why i only open a container over a water catchment when it contains mercury.

I demagnetised the residue with n52. Decided seen as mercury was present id add more and amalgamate everything what will amalgamate.
Mercury sits on top of this stuff whats left. Ive removed it and dried the residue and this is whats left

 

[im1badpup1]

Thanks all who have helped n give me good advice and tips. Im about at the end of my thread now, if i start anymore il try be a bit more informative and better presented with my posts. Makes things easier for people whose first language isnt english.

Does anyone want any information about the goldcube i mean if youve any ideas to change things around and improve or maximise its performance for certain conditions?
Id be happy to run some tests with it and post results.
Im thinking about to classify and size material and run the pump at a certain rate.

Because all my gold is small im going to reduce material size i feed and slow flow rate to see if i can increase capture rates. Beachgold like mine is apparantly difficult to capture been very small smooth flat pieces.

 

[cosmetal]

Thanks all who have helped n give me good advice and tips. Im about at the end of my thread now, if i start anymore il try be a bit more informative and better presented with my posts. Makes things easier for people whose first language isnt english.

Does anyone want any information about the goldcube i mean if youve any ideas to change things around and improve or maximise its performance for certain conditions?
Id be happy to run some tests with it and post results.
Im thinking about to classify and size material and run the pump at a certain rate.

Because all my gold is small im going to reduce material size i feed and slow flow rate to see if i can increase capture rates. Beachgold like mine is apparantly difficult to capture been very small smooth flat pieces.

I enjoyed the thread.

I was hoping that what you first showed us was coming from a flowing water source - my personal experience with placer gold is more relevant to that environment.

Not to add too many questions to a closing thread, but, have you any experience with a Blue Bowl or Miller Table? They work slower than the Cube and will keep more of the fines. As you said, the Cube is a super concentrator. So, when you're onsite, "super concentrate" into some sort of catch basin and finish those basin cons with a bowl or table offsite where you're warm and have a pint next to you! :wink:

Peace!
James

 

[im1badpup1]

Thanks james i do have a river/estuary location i tried once its just wrong time of year to go there. Theres a clay silt deposit on the blacksand concentrate what clears best in late spring when rain washes it clean.

No ive no experience with miller tables or blue bowls. I keep looking at them and similar on u tube in operation. Theyre a cleanup tool really?
Ive been more focused on concentrators to get a worthwhile concentrate to process further. Im still debating with myself at what point do i cutoff concentrating and separating the easy material and chemically extract and purify the rest.
Im not sure if a miller table or bluebowl will separate lead and gold effectively and i really doubt it can separate pgms. All ive seen what separated lead and gold so far is a shaker table and again this still left remaining inseparable concentrate.

Im looking into the chemical processes involved in separation and purifaction more now too.
For me to separate gold from pgms id amalgamate the gold.
Ive got a lot of lead in my concentrate and it contains precious metals from what i can determine when i did a cupellation on it. But to separate from the gold i guess most convenient is dissolve in hydrochloric acid.

Ive not checked my sulfides for precious metals yet if my elemental leads argentiferous theres hope for the galena, i was thinking of adapting whats on this research paper to extract the values,
CHLORIDE–HYPOCHLORITE OXIDATION AND LEACHING OF REFRACTORY SULFIDE GOLD CONCENTRATE Mehdi Ghobeiti HASAB, Fereshteh RASHCHI, Shahram RAYGAN
Sorry i cant paste a link with this phone.
I used to do a similar but more complex reaction years ago 82% what they got is easy the reaction becomes hindered at about 90-92% but given this is far simpler in mechanism it could give higher.
I would say this reaction runs best dilute at lower temperatures giving time for the multiple chlorination to take place and prevent cl from escaping into the atmosphere. Preparation is key the material must be finely divided.
It makes far more sense than what ive been reading about adding hcl and ph of 3-4 what has been confusing the hell out of me.

Id be left with a bunch of metal chlorides in solution. And chlorides non soluble but either way i can separate them now.

 

[cosmetal]

Both the Blue Bowl and The Miller Table will help to further concentrate your material depending upon how fast you set up your water flow. They're both good tools to get rid of the more base metals with lower densities than Pb and the PMs, especially if you're going to use wet chemical methods for final refining. Plus, if you're handy, you can build your own models. As you no doubt know, for refining, "the cleaner the better".

"i do have a river/estuary location i tried once its just wrong time of year to go there".

I bet you didn't use a 4" or 6" suction dredge with a hookah air set-up and a black sand concentrator on the end of the main sluice. Also, a power winch with a rock sling would be nice. From what I have seen of your gold, I would love to be on your river/estuary with either of them! Look out bedrock!

Ah! The memories . . . !

 

[cuchugold]

I'm still debating with myself at what point do i cutoff concentrating and separating the easy material and chemically extract and purify the rest.

I think the cutoff is between 150 and 250 mesh. Notice that probably all of the gangue above 150 mesh is worthless after gravity concentration, so you only need to process chemically the stuff smaller than that, which is always a small % of the original amount of material. Probably the best route is to accumulate it to chemically process when a certain estimated amount of $ are in there. Sieving gives you a real good idea of what values are at what size. (Deano's idea).