❓Your Mineral Identification Questions answered here

[Powerhammer]

Thanks for having a look goldierocks

I thought the same but it is all through the rock and I have seen the same structure in multiple rock samples, some from WA and some from SE Queensland.
My thought was that as the hot fluids passed through the rocks it deposited microscopic branches if the host rock was porous enough.

Do you think the rock is Metamorphic?

Because I have seen the structure a few times I thought it common and could find out more about it but that's not the case. I've searched the internet quiet a bit and haven't found anything that describes it.

I did have a sample with the same thread structure assayed from really close to Perth and had really high values of copper but no gold.

My thought is that its some form of copper, they behave like a metal wire when I bend them with a probe.

I'll get it assayed in the next few weeks and post the results.

 

[Mr Magoo]

My thought is that its some form of copper, they behave like a metal wire when I bend them with a probe.

Does the 'wire' burn? Flame colour?

 

[Powerhammer]

Took your advice Mr Magoo and took to it with the Creme Brulee torch and low and behold puddles of metal.
I've circled the puddles and yep another iphone shot down the eyepiece
Didn't burn with a green flame or any colour, might not have had enough heat to vaporise
seems to be enough metal to fuse though.

 

[Mr Magoo]

That's all my pearls of wisdom exhausted.
I'll return to my back seat and await the result then.

 

[Powerhammer]

Hi All
Split another sample open today and got the same thread formation
I've marked "A" as the metallic inclusion and "B" as the thread and changed the focal length of the same image on the microscope.
You can see the thread clearly in the First image.
This thread goes to a similar silver metallic inclusion.
The inclusion seems to spread easily with metal probe and coats nearby particles
Any ideas what it could be?

 

[Powerhammer]

Image of when I smeared it with the probe and another of the rock it came from.
This rock was found about 10m away from the red one in my earlier posts

 

[user 4386]

This has me beaten, despite excellent photos.

 

[Powerhammer]

Thanks for having another look Goldie rocks.
I have a very good microscope and the images are highly magnified and the metallic spot is only 0.2mm .
Some of the threads definitely seem metallic but the others seem to be white which I'm thinking is some sort of natural flux residue that aids in the deposition process.
Using the probe I removed it from the metallic inclusion and it was attached through the reddish oxidised zone was like a river delta system . To me it looks like the metal had been transported through these thread structures an then deposited.
I dropped both rocks off to be fire assayed and a 4 acid digest (FA25/ms and 4A/OE33 at Intertek Genalysis) yesterday and it will be 2 weeks before I get the results.
I will post the results when I get them in.

It amazed me how well the photos came out using a IPhone shooting down the eye piece of the microscope

Also really appreciate your effort with your resent posts on mineral identification and sharing your knowledge :Y:

 

[user 4386]

Thanks for having another look Goldie rocks.
I have a very good microscope and the images are highly magnified and the metallic spot is only 0.2mm .
Some of the threads definitely seem metallic but the others seem to be white which I'm thinking is some sort of natural flux residue that aids in the deposition process.
Using the probe I removed it from the metallic inclusion and it was attached through the reddish oxidised zone was like a river delta system . To me it looks like the metal had been transported through these thread structures an then deposited.
I dropped both rocks off to be fire assayed and a 4 acid digest (FA25/ms and 4A/OE33 at Intertek Genalysis) yesterday and it will be 2 weeks before I get the results.
I will post the results when I get them in.

It amazed me how well the photos came out using a IPhone shooting down the eye piece of the microscope

Also really appreciate your effort with your resent posts on mineral identification and sharing your knowledge :Y:

Pl4ased to help where I can, but those threads have me fooled - I don't know what to make of them.

 

[samrota]

I know it can be difficult to identify minerals from pictures alone, but was wondering if anyone had any idea what this could be or how I can identify it. Cant seem to scratch it with a sharp knife. Very glassy looking and dark green. Found near Adelaide Airport yesterday. Could it be slag or melted glass of some description.

Thanks for any help.

 

[Mungoman]

Serpentine?

 

[Powerhammer]

Hello All

As promised got the assay reports back this morning (See below)
Sample RG1 is the red rock that was in the previous posts with the thread formations
Sample RG2 is the white and black rock sample previously posted.
The WSP1 & 2 are samples from a different location about 10km apart

Goldierocks, it seems these samples have high values in titanium and some other element, I am interested in how a Geoligist would interpret these values and if further investigation should be done via coredrill etc. Basically what a professional in the feild would do?

Is even a slight sniff at ppb for Pd and Pt in a surface floater rock sample worth investigating the area further?

https://www.prospectingaustralia.com/forum/doc/member-docs/13181/1534937124_binder1.pdf]

 

[user 4386]

Serpentine?

Not if it is so hard (otherwise it might have been a possibility)

 

[user 4386]

Hello All

As promised got the assay reports back this morning (See below)
Sample RG1 is the red rock that was in the previous posts with the thread formations
Sample RG2 is the white and black rock sample previously posted.
The WSP1 & 2 are samples from a different location about 10km apart

Goldierocks, it seems these samples have high values in titanium and some other element, I am interested in how a Geoligist would interpret these values and if further investigation should be done via coredrill etc. Basically what a professional in the feild would do?

Is even a slight sniff at ppb for Pd and Pt in a surface floater rock sample worth investigating the area further?

https://www.prospectingaustralia.com/forum/doc/member-docs/13181/1534937124_binder1.pdf]

Too much searching - i.e. relating rocks to assays, need totals from analyses (since Si not determined - it will be most of the balance I would think). High Ti is in the eye of the beholder a bit (even black slate can exceed 1% Ti) - one needs to look at it in conjunction with Ni, Cr etc. (the low The high iron sample is fairly obvious.

Sorry, too time consuming - if you show small representative images of the samples with their sample numbers next to them, and tabulate the analyses into a simple table with totals, I will have another look. e.g. 560 ppm = 0.056% etc. I would only include elements equal or greater than 1000 ppm = 0.1% in your table. Your analyses will hold the answer, and I could give you the reasoning.

I would not be interested in those Pt and Pd values - they simply mean that they can just be detected, not that they are obvious (refer to detection limits). Even if they were ten times that they would suggest little, in rocks so low in Mg, Ni and Cr.

 

[Powerhammer]

Hello All

Thanks for having a look Goldierocks would appreciate your thoughts.https://www.prospectingaustralia.com/forum/doc/member-docs/13181/1535078886_assay_doc.pdf

 

[user 4386]

Hello All

Thanks for having a look Goldierocks would appreciate your thoughts.https://www.prospectingaustralia.com/forum/doc/member-docs/13181/1535078886_assay_doc.pdf

I have totalled them, and all except RG1 appear to be nearly all Si (probably mostly as quartz) - RG2 almost entirely so. Obviously oxygen makes up part of the balance but it is low mass (and I don't have time to recalculate things like Mg, Fe, Al, K, Na and Ca to their oxides). Unfortunately the photos are not useful (and your original larger photos are not identified by sample number), so I will confine myself to chemistry.

Without knowing sample numbers, your large photos look partly to be quartz- white mica- K feldspar rocks, such as quartz schists and micaceous quartzites, probably with some Fe minerals (biotite mica, iron oxides)? So original sedimentary rocks now converted to metamorphic rocks. RG2 is essentially quartz only. The low Mg rules out truly mafic rocks like volcanics, despite the high iron. The high Al and K are consistent with micas and feldspars. Higher Ti in all except RG2 probably reflect micas , as do Ba and F (P could also be traces of the mineral apatite, not uncommon in siliceous sediments). Rare Earth Element (REE) concentrations are not unusual (probably in "heavy" minerals, common in siliceous metasediments).

So the only very different rock is RG1, with 33.8% Fe, 364 ppm Cr, 375 ppm Cu, 76 ppm Pb, 149 ppm Zn, 410 ppm V but no Mg, K, Na and obviously lower Si. The low Mg and Ni rule out a mafic rock like metabasalt, serpentinite etc., so I imagine the Cr reflects "heavy" minerals from an original sediment - ditto with V (now in micas), I could probably say more from appearance of the rock if I had a good, large detailed photo. If it is a weathering product like laterite the high Cu and slightly elevated Pb and Zn are probably of limited interest (375 ppm Cu is definitely a bit anomalous though) - if an unweathered rock they would definitely be anomalous, occurring together as they do. The fact that Pt and Pd are just detected in this sample (but of no interest) may reflect the current or former presence of base metals (Cu, Pb, Zn), or may just be an analytical artefact related to the elevated iron.

That gives you some idea of how analyses can be used.

 

[Powerhammer]

Hi Goldierocks

Thanks for your insight, I have attached a photo of RG1 as well as a magnified surface image of the specimen

 

[user 4386]

It looks like it could be a similar rock but with a very high percentage of limonite (iron oxides). While not spectacularly anomalous, it could be from a mineralised area.

 

[Mirrors]

Hi all, as you can notice I'm new to the forum and yesterday while out prospecting I found this in the pan (avatar picture )
It has 4 sides on each point with 4 flat sides.
I have no idea about crystals so any info would be appreciated.

 

[Heatho]

A bit of a better close up photo would help, though it does look like quartz to me, quartz crystals are usually hexagonal with 6 sides though.

Welcome to the forum.