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Native silver in quartz ?

Posted by Heath Barnes  
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Heath Barnes May 04, 2012 08:21PM
I found this recently while excavating an as yet unknown gravel bed i descovered a year ago in my local area, i think it may be native silver in quartz any help would be very welcome.
open | download - DSCF0933-001.JPG (94.5 KB)
open | download - DSCF0937-001.JPG (95.7 KB)
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Rob Woodside May 04, 2012 08:27PM
Is it maleable?
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Heath Barnes May 04, 2012 08:34PM
To be honest i have been reluctent to mess with it ive only washed it since digging it from the gravel beds, the bits of tarnished stuff crush easily, and the brighter silver looking material indents easily if thats the right word ? The vein is very thick and can i think be seen through some of the clearer quartz.
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Rob Woodside May 04, 2012 08:37PM
You can poke it with a needle and see if it digs a tiny trench
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Don Saathoff May 04, 2012 08:42PM
Heath, remember that native silver is a soft metal and will act like a soft metal if scratched or cut or hammered.....

Don
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Maggie Wilson May 04, 2012 08:53PM
Hi Heath - is your local area known to have native silver?
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Heath Barnes May 04, 2012 09:02PM
Not that i know of but ive found a lot of matereal in these gravel beds that does not belong here, glacial activivity is the proberble answer, but its must have been a gentle process ie aluvial not buldozed till. The silver matereal dose give quite easily to pressure by the end of a needle, the veins on the other side are not as thick, but are gold in apearance?
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Heath Barnes May 04, 2012 09:59PM
These pieces were found in the same 3 metre square section of excavated gravel bed.
open | download - DSCF0064-001.JPG (88.8 KB)
open | download - DSCF0527-001.JPG (89.8 KB)
open | download - DV000061-001.JPG (84 KB)
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Paul Brandes May 04, 2012 11:30PM
To me, it looks like a piece of quartz with silvery mica running through it, maybe from a granite or granitoid rock originally. You mentioned Heath that there are a lot of rocks that do not belong there, which is a good indicator of glacial activity. Judging by the appearence your rock didn't travel far, so if you could figure out where a glacier may have come from, you could backtrack and possibly find the source of your rock.



Edited 1 time(s). Last edit at 05/04/2012 11:31PM by Paul Brandes.
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Heath Barnes May 05, 2012 08:12AM
Paul Brandes Wrote:
-------------------------------------------------------
> To me, it looks like a piece of quartz with
> silvery mica running through it, maybe from a
> granite or granitoid rock originally. You
> mentioned Heath that there are a lot of rocks that
> do not belong there, which is a good indicator of
> glacial activity. Judging by the appearence your
> rock didn't travel far, so if you could figure out
> where a glacier may have come from, you could
> backtrack and possibly find the source of your
> rock.


Thanks for the input Paul is there any test i can do to find out if the material is mica or native silver ? As for the glacial activity around here its thought that three major ice flows converged on this area but a lot of what is stated seems to be hit and hope if you get my meaning, and since ive been excavating this area its got a whole lot more confusing ( complicated ! )
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Heath Barnes May 05, 2012 08:59AM
Ive checked best i can with mica examples, but to my untrained eye mica apears layered, this material almost looks to have grown through the quartze like roots or even as if it was molten and flowed through ?
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Uwe Ludwig May 05, 2012 09:26AM
I don't think that the silver shining mineral is native silver. Silver in a gravel bed, open to the influence of the ground water becomes black and the layer of the black akanthite can not be removed simply by washing the piece. Native silver is arising hydrothermal - in this case you will find sliver curls or crystalls in a mini pocket of the quartz or it is arising by weathering of a sulfide containing vein - in this case it is accompanied with limonite or carbonates.

Uwe Ludwig
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claire Brimson May 05, 2012 10:50AM
Hi Heath

I would agree with Uwe that it is not Silver as this element would generally oxidize on exposure to air and turn black. Heath... If you rub your finger across the 'silvery-pearly' bits, do you get a pearly like finger? (A bit like the stuff women wear on their eyes - eye powder). Also, is the texture silky? pearly? greasy? Where abouts are you based/gravel bed based please?


Claire
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Rob Woodside May 05, 2012 03:01PM
Uwe is quite right. Attack it with a needle and see if tiny plates result, then you probably have a mica. The plates should be elastic.

The last of your 3 pictures looks like a flint nodule. Similar nodules can be found along the Atlantic coast, They were ballast from England and dumped to take on cargo for the mother country.
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Uwe Ludwig May 05, 2012 04:53PM
Interesting what Rob told regarding the flintstones. Is it true that there are no natural flint deposits along the North American Atlantic coast ?

Uwe Ludwig
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Rob Woodside May 05, 2012 06:19PM
That is what I have been told. The white rind is suppposed to be from English Chalk deposits.
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Heath Barnes May 05, 2012 07:05PM
Uwe Ludwig Wrote:
-------------------------------------------------------
> I don't think that the silver shining mineral is
> native silver. Silver in a gravel bed, open to the
> influence of the ground water becomes black and
> the layer of the black akanthite can not be
> removed simply by washing the piece. Native silver
> is arising hydrothermal - in this case you will
> find sliver curls or crystalls in a mini pocket of
> the quartz or it is arising by weathering of a
> sulfide containing vein - in this case it is
> accompanied with limonite or carbonates.
>
> Uwe Ludwig
Funny you should say that Uwe most of the material is black and boy ive tried allsorts including the baking soda and alaminium idea but it still won't shift, but when rubbed the blacker stuff shines very nice, whatever the material is it is all the same the tarnished black and bright silver pieces.
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Heath Barnes May 05, 2012 07:16PM
claire Brimson Wrote:
-------------------------------------------------------
> Hi Heath
>
> I would agree with Uwe that it is not Silver as
> this element would generally oxidize on exposure
> to air and turn black. Heath... If you rub your
> finger across the 'silvery-pearly' bits, do you
> get a pearly like finger? (A bit like the stuff
> women wear on their eyes - eye powder). Also, is
> the texture silky? pearly? greasy? Where abouts
> are you based/gravel bed based please?
>
>
> Claire Thanks for the help Clair as for rubbing the material leaves no streak of any kind on the skin, The streak on the pack of a tile is bright silver from the brighter material and goldy silver from the tarnished majority, the texture at the moment ie without any polishing is a bit course, apart from one bulbouse piece wich is very smooth. I will try to take some new pics and post soon, again thanks for the help.
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Heath Barnes May 05, 2012 07:20PM
claire Brimson Wrote:
-------------------------------------------------------
> Hi Heath
>
> I would agree with Uwe that it is not Silver as
> this element would generally oxidize on exposure
> to air and turn black. Heath... If you rub your
> finger across the 'silvery-pearly' bits, do you
> get a pearly like finger? (A bit like the stuff
> women wear on their eyes - eye powder). Also, is
> the texture silky? pearly? greasy? Where abouts
> are you based/gravel bed based please?
>
>
> Claire Sorry forgot to say Clair ime from Teeside in north east England, the best way to understand the beds would be to visit my blog at historyofabeckblogspot.co.uk
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Rob Woodside May 05, 2012 07:27PM
Ahh! Teeside! That explains the English Flint.
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Heath Barnes May 05, 2012 07:29PM
Rob Woodside Wrote:
-------------------------------------------------------
> Uwe is quite right. Attack it with a needle and
> see if tiny plates result, then you probably have
> a mica. The plates should be elastic. No plates Rob the material thats not tarnished comes away quite easily with a needle, the tarnished stuff is tuffer but again does shift with the needle, as ive said to Claire ime gonna try get some better pics posted of all sides, thanks for help, i wish ide found the site before now.
>
> The last of your 3 pictures looks like a flint
> nodule. Similar nodules can be found along the
> Atlantic coast, They were ballast from England and
> dumped to take on cargo for the mother country. The last is as you say a flint burrow nodule, this one never made the boat though;winking smiley
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Alfredo Petrov May 05, 2012 07:29PM
1) Quartz + mica cobble.
2) Hematite pebble, perhaps?
3) Septarian concretion.
4) Flint.
The latter two are quite nice specimens smileys with beer
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Heath Barnes May 05, 2012 07:32PM
Rob Woodside Wrote:
-------------------------------------------------------
> That is what I have been told. The white rind is
> suppposed to be from English Chalk deposits.Thats the story as ive heard it Rob, thing is we aint got no chalk cliffs round here there in the south were we defenetly aint had no ice flows from !
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Rob Woodside May 05, 2012 07:32PM
Alfredo nailed 3
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Rob Woodside May 05, 2012 07:33PM
I don't really know but maybe the glaciers ate the chalk???
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Heath Barnes May 05, 2012 07:35PM
Yea Rob i think i need one of them flags eh !
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Heath Barnes May 05, 2012 10:25PM
Here are some improved pics hopefully plus some other items hope ime not putting too many on ?
open | download - DSCF1077-001.JPG (125.4 KB)
open | download - DSCF1081-001.JPG (116.1 KB)
open | download - DSCF1075-001.JPG (102.9 KB)
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Heath Barnes May 05, 2012 10:47PM
And the rest ps is there any probs posting more as i have plenty iide like to show and learn more about ?
open | download - DSCF1085-002.JPG (109 KB)
open | download - DSCF1093-001.JPG (77.9 KB)
open | download - DSCF1096-001.JPG (74.6 KB)
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Don Saathoff May 06, 2012 12:45AM
Hello Heath,
We don't know how much experience you have had with chemistry or whether or not you have access to a chemist......BUT, a sure test for silver is to dissolve the metal in a ~25% solution of Nitric acid kept warm in a glass container (no need to boil and only a small fragment is needed). After the metal has disolved, add some Muriatic acid (a small amount.....or common table salt). If a feathery white precipitate forms, you have either silver or lead. Let the precipitate settle, pour off the liquid, and add a quantity of warm water greater than the amount of liquid left in the container. If the feathery precipitate dissolves in the warm water, you have lead....if the precipitate doesen't dissove you probably have silver. If you filter off the precipitate (with a coffee filter), put it in the sun, if it is silver it will turn dark lavender or even black. The key to this procedure is the temperature of the water you add - Silver Chloride is insoluble in hot water whereas Lead Chloride is soluble.

Good luck & have fun!!!

Don S.
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claire Brimson May 06, 2012 07:04AM
Heath - I like your blog, it is cool and very very interesting!

I hate to put a spanner in the works, but I dont think it is chalk or flint. I have been to the southern england area of chalks and flints and your peice is nothing like that. I reckon yours is quartz (or calcite) with phyllosilicote (mica grp) - nice though; the black bit, I dont know. The rectangle pebble is nice, very nice. Haematite iron with a thin vein of ..... running through it giving it a weakest point of fracture.

In Teeside, there is a geology mueseum? or the university runs geology? Could they be helpful to you? I know that over here in Oulu, the geology museum and university have been very helpful - they even speak english!

Happy digging and finding

Claire
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Heath Barnes May 06, 2012 01:06PM
Don Saathoff Wrote:
-------------------------------------------------------
> Hello Heath,
> We don't know how much experience you have had
> with chemistry or whether or not you have access
> to a chemist......BUT, a sure test for silver is
> to dissolve the metal in a ~25% solution of Nitric
> acid kept warm in a glass container (no need to
> boil and only a small fragment is needed). After
> the metal has disolved, add some Muriatic acid (a
> small amount.....or common table salt). If a
> feathery white precipitate forms, you have either
> silver or lead. Let the precipitate settle, pour
> off the liquid, and add a quantity of warm water
> greater than the amount of liquid left in the Thanks for that Don and i will attempt the procedure, but ime far from experienced in chemistry!
> container. If the feathery precipitate dissolves
> in the warm water, you have lead....if the
> precipitate doesen't dissove you probably have
> silver. If you filter off the precipitate (with a
> coffee filter), put it in the sun, if it is silver
> it will turn dark lavender or even black. The key
> to this procedure is the temperature of the water
> you add - Silver Chloride is insoluble in hot
> water whereas Lead Chloride is soluble.
>
> Good luck & have fun!!!
>
> Don S.
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Heath Barnes May 06, 2012 01:24PM
claire Brimson Wrote:
-------------------------------------------------------
> Heath - I like your blog, it is cool and very very
> interesting!
>
> I hate to put a spanner in the works, but I dont
> think it is chalk or flint. I have been to the
> southern england area of chalks and flints and
> your peice is nothing like that. I reckon yours
> is quartz (or calcite) with phyllosilicote (mica
> grp) - nice though; the black bit, I dont know.
> The rectangle pebble is nice, very nice.
> Haematite iron with a thin vein of ..... running
> through it giving it a weakest point of fracture. Thanks Clair to be honest the blogs a bit rough and theres proberbly incorrect posts early on, its been a learning proscess, ! I use the blog as a record for myself so that doesn't help its presentation i suppose, ile sort it out one day !winking smiley
The gravel beds ive uncovered are a mystery at the moment, ive got the help of a couple of local geologists, and we have done quite a bit of work yet we seem to uncover more questions than answers. ie I have descovered the near by Cleveland dyke ( Basaltic Andasite) quite easily attracts a small magnet, and that the gravel beds contain lots of it, along with other unidentified magnetic material other than load stone. The beds seem for some reason to remarkably preserve both organic and mineral material including bone and carboniferous - jurassic and triassic fossils.

>
>
> In Teeside, there is a geology mueseum? or the
> university runs geology? Could they be helpful to
> you? I know that over here in Oulu, the geology
> museum and university have been very helpful -
> they even speak english!
>
> Happy digging and finding
>
> Claire
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Heath Barnes May 06, 2012 01:41PM
This piece i can never seem to get close enough to do the crystals justice, when moved the crystals realy come to life if ya get my meaning, the matrix is very hard and i think but am not experience to know for sure! seem pentagonal.
open | download - DSCF1089-002.JPG (92.4 KB)
open | download - DSCF1091-002.JPG (87.9 KB)
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Rob Woodside May 06, 2012 06:26PM
Thanks for the new pictures. It is definately not Silver. Perhaps an amphibole? What is its hardness?

Claire, why do think this is not flint?
http://www.mindat.org/forum.php?file,11,file=38163,filename=DV000061-001.JPG
Heath says the purported silver does not produce micaceous flakes, I agree with you that it does look like some kind of mica..
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Heath Barnes May 06, 2012 06:43PM
Thanks Rob can you tell me why you are sure its not silver is it the new pics that have made your mind up ? and also do you know the best method of cleaning the quartze ie is there a way of making it more clear as the silver material can be seen through it at the top.
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Heath Barnes May 06, 2012 06:46PM
Heath Barnes Wrote:
-------------------------------------------------------
> Thanks Rob can you tell me why you are sure its
> not silver is it the new pics that have made your
> mind up ? and also do you know the best method of
> cleaning the quartze ie is there a way of making
> it more clear as the silver material can be seen
> through it at the top.
Forgot Rob how best can i tell its hardness ime really new to this?
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Heath Barnes May 06, 2012 07:21PM
Rob it scratches steel and and fingernails but not glass 6-7 ?
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Rob Woodside May 06, 2012 07:50PM
The new pictures show that th 'Ag' is too white and it has the foliated texture of mica group.

Tiny inclusions make quartz milky, just as water droplets make clouds white. Sadly you can't render milky quartz clear.

I've been criticized for suggesting hardness tests and there was talk of making a video or at least a good description, but I don't know if this was ever done. Mohs developed the hardness scale in the early 19th century and its ease and simplicity make it, with streak, still the first line of attack when identifying minerals.

First as with streak, pick an inconspicuous spot to do the test, say on the back or broken surface. Do not destroy good specimens by testing on good xl faces leaving bruises and gouges on what would have been an aesthetic specimen. (You needn't worry too much about this "Ag")

The Mohs scale from 1 to 10 is based on what will scratch what and starts with the softest and ends with the hardest..
1 Talc
2 gypsum,
3 calcite
3 fluorite
5 apatite
6 feldspar
7 Quartz
8 Topaz
9 corundum
10 diamond
You can buy commercial hardness points, but I'm not sure how long they would last and give no better results than small pieces of these minerals that one accumulates. Until you get such you can use a finger nail (about 2), copper penny (these are scarce now, hardness is 3) Steel knife (5), Window glass (5.5, Mohs hardness is only reported to the nearest 0.5)

To measure hardness you need a pointy bit on the scratcher and a flatish bit on the scratchee. Then firmly try to make a scratch on the flattish bit. Splintery (such as your "Ag") or powdery minerals may appear to be scratched by something softer, so beware. You can sort this out by reversing the scratcher and scratchee or approaching the hardness from above or below. You must also make sure that you do have a scratch and not a line of debris. So rub the purported scratch to remove debris and try to catch the scratch with your thumbnail. If your nail catches on the scratch you have a real one. Some minerals, possibly your "Ag", may have a softer altered surface so a fresh surface is best. This is a petty crude way of determining toughness of a mineral and so although many minerals are slightly harder in one direction of an xl than another, the Mohs test usually misses this . A notable exeception is Kyanite, formerly known for this reason as Disthene,
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Rob Woodside May 06, 2012 07:54PM
Scratches steel but not glass, so he hardness is about 5. Silver streak with hardness 5. Could be an amphibole, but other may have better ideas.
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Heath Barnes May 06, 2012 08:41PM
Don't know if this helps but the piece weighs just short of 6 lb i woul say the quartz silver material are not far from equal in the total mass, hope that makes sence!
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D Mike Reinke May 06, 2012 11:11PM
Heath,
You've got the weight, if you can get the volume, you can get the specific gravity, SG, which tells a lot. SG of silver is @ 10, '10x heavier than water', quartz is @2.6. 2.7 is mica. If it is half silver, it should feel distinctly heavier than a quartz chunk of same size. If you have a measuring cup w/ marks on the side, submerge it in water, see the amount, remove it and see what is left. The diff. is the volume. there is a thread on how to get SG here on mindat too. That would be even better to consult.
Either way, this is only a ballpark figure, but if you're new, like me, (and underfunded like me!) it is a good start. You can only estimate the SG since you can't know the exact percentage of quartz you have. So if your SG is anywhere near 3, assuming it is half quartz, you have no Ag, if it is around 6, you may have half silver, half quartz. Or another heavy mineral is in there. Make sense??! Hope this helps!
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Jim Bean May 07, 2012 01:12AM
Those last two photos remind me of Trinitite.
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Rock Currier May 07, 2012 02:23AM
Has anyone written an article about hardness and SG testing that we could point people to?

Rock Currier
Crystals not pistols.
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Heath Barnes May 07, 2012 11:32AM
Jim Bean Wrote:
-------------------------------------------------------
> Those last two photos remind me of Trinitite.
Jim its the first ive heard of Trinitite, its all new to me but after reading up on it and viewing images i see what you mean, at first i thought it must be Flurite but then realised its far to hard it scratches steel very easily aswell as glass, it was dug from a previously unknown gravel bed i descovered while excavating in my local area. The beds are at least 15.000 years old, could the near by Cleveland dyke event have caused a simmiler enviroment in the rocks it intruded?
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Heath Barnes May 07, 2012 11:48AM
Thanks to all and sorry if ive not directly replyed to a post, ime still trying to take it all on board!winking smiley
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claire Brimson May 07, 2012 05:15PM
Rob Woodside Wrote:
-------------------------------------------------------
> Thanks for the new pictures. It is definately not
> Silver. Perhaps an amphibole? What is its
> hardness?
>
> Claire, why do think this is not flint?
> http://www.mindat.org/forum.php?file,11,file=38163
> ,filename=DV000061-001.JPG
> Heath says the purported silver does not produce
> micaceous flakes, I agree with you that it does
> look like some kind of mica..

Apologies for not getting back sooner, I am on night rotation for a few days. My reason for not thinking it was flint or chalk is because having seen the flint and chalk beds of the South Downs (GB), and also having some back at home, this peice does not look like it. However, I do not mind being proved wrong... The crystaline peice on the top appears white and looks like it has definate clevage lines, flint and chalk appear not to have these and are only cystaline under microscope. However, I do think it is an interesting conundrum.... Hope this helps!
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Heath Barnes May 07, 2012 06:58PM
Rob - Claire the geologists helping me have viewed the nodule and seemed quite sure it was flint, heres a pic of the other side, it does have some wierd looking stuff on the darker surface. and by what ive read are still not fully understood. ?
open | download - DSCF1111-001.JPG (77.5 KB)
open | download - DSCF1115-001.JPG (78 KB)
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Heath Barnes May 07, 2012 07:09PM
D Mike Reinke Wrote:
-------------------------------------------------------
> Heath,
> You've got the weight, if you can get the volume,
> you can get the specific gravity, SG, which tells
> a lot. SG of silver is @ 10, '10x heavier than
> water', quartz is @2.6. 2.7 is mica. If it is
> half silver, it should feel distinctly heavier
> than a quartz chunk of same size. If you have a
> measuring cup w/ marks on the side, submerge it in
> water, see the amount, remove it and see what is
> left. The diff. is the volume. there is a thread
> on how to get SG here on mindat too. That would
> be even better to consult.
> Either way, this is only a ballpark figure, but if
> you're new, like me, (and underfunded like me!) it
> is a good start. You can only estimate the SG
> since you can't know the exact percentage of
> quartz you have. So if your SG is anywhere near
> 3, assuming it is half quartz, you have no Ag, if
> it is around 6, you may have half silver, half
> quartz. Or another heavy mineral is in there.
> Make sense??! Hope this helps!


Mike i hope ive done this right if so the volume is 1070 ml so now how do i get the sg ?
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Rob Woodside May 07, 2012 07:31PM
6 lbs / 2.2 lb/kg = 3 kg = 3000 gm

1070 ml = 1000 cm3

3000 gm / 1000 cm3 = 3 gm /cm3

So specific gravity = density of substance / density of water = (3 gm/cm3) / (1 gm/cm3) = 3

So roughly (to 1 significant figure) the specific gravity of your "Ag" is 3. That is too low for a rock that is half Silver as Mike says.
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Heath Barnes May 07, 2012 08:18PM
Thanks for that Rob and hopefully i will eventually understand ! i would love this piece to be silver and quartz for obviouse reasons ! winking smiley but i realy just whant to know what it is as it will help my research, and maybee fill one of the gaping holes ime having to jump across at the moment.
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Alfredo Petrov May 07, 2012 08:38PM
Mistaking shiny mica for silver or gold has been very common historically, so don't feel too bad about it. Read the great book "Roughing It", by Mark Twain. There's a funny chapter where he describes how he mistook a bunch of mica flakes for a rich gold deposit. And Silver Mine in Bear Mountain State Park, New York, is just a mica-bearing quartz locality. So you're far from alone, Heath.
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Heath Barnes May 07, 2012 09:09PM
Yes ive learned a lot being wrong as this is the only way, ime still not totally convinced its mica as it definatly does not have laminations of any kind when disturbed with a needle it just crumbles into a silver sparkling soft dust ?
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Heath Barnes May 07, 2012 10:47PM
Also can anyone tell me of a mica that scratches steel ? like this stuff ?
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Alfredo Petrov May 07, 2012 11:52PM
Quartz impurities mixed into the mica scratch the steel, not the mica itself.
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D Mike Reinke May 08, 2012 03:16AM
Heath,
Try getting a few 'beginner' rock books at a library, and don't be ashamed they are for beginners, this is a deep subject, and get a few, because each will explain things a little different, and each will add to your awareness. I for one, never gave a second thought what is under my feet, and now it is a brave new world, in a good sense. And w/ book in hand, keep mindat on your screen when reading, to compare pictures, posts, etc. Very helpful. Enjoy.
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Stephanie Martin May 08, 2012 03:54AM
Here is the link to the thread that discusses how to perfom SG tests. Yes, this seems to be a recurring request and would be nice if pinned somewhere. There are a few variations of the method, some being more technically accurate. But for smaller sized pieces and ease of execution, the method that Reiner describes is normally accurate enough to get a helpful result. The density information can then be found on the mineral data page for the mineral that you are trying to ID. So you can compare as above if the SG is in the correct range for your suspected mineral as in the silver above. If it is not close then you know you have something else.

http://www.mindat.org/forum.php?read,11,250282,page=1

Hope this helps.
regards,
stephanie smiling smiley
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Heath Barnes May 08, 2012 08:22PM
Thanks for all the help its been an eye opener for me, and please i hope ive not offended anyone i tend to question everything ! winking smiley
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Becky Coulson May 12, 2012 08:00PM
Hi Heath, I just read through this thread...the flint nodule is a typical piece of flint with a chalk "rind". It's found all over the east coast and southern England. Anyone heard of the White Cliffs of Dover? They are chalk (Cretaceous, I think) full of such black/gray flint, as are cliffs further north on the east coast. It is also found deposited all along the coast from ships' ballast and from undersea exposures, and has been dragged here and there by glaciers.

Heath, I'm curious about your research in the Cleveland area. What are you researching? Cheers, Becky
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Heath Barnes May 12, 2012 08:35PM
Hi Becky firstly the correct discription is flint burrow nodule and yes they are found in the south east of England, but as ive said not fully understood they are thought to be remnents of some of the planets eariest life forms. As for my so called research ime an ordinary man who decided one day that what he found beneath his feet did not match what it was said to be, then in the early days was patronised quite a bit by the experts but have now a year and a bit got them sitting in the shadows not quite sure what to say to me!
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Heath Barnes May 12, 2012 09:16PM
The more i look at this stuff the more ime convinced its not mica of any kind, its not layered in any way, also ive attempted cleaning it according to the native silver method on another thread and it has helped but is not doing a lot to the darker pieces, please could anyone who believes it or are sure its mica show me images of similer pieces ?
open | download - DSCF1145-001.JPG (115.5 KB)
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Amanda Hawkins May 14, 2012 06:31PM
Is it graphite? If you can dent it with your finger nail it could be? I had some emerald with very soft silvery grey graphite, it could easily be dented with a finger nail.

Amanda
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Heath Barnes May 14, 2012 07:50PM
No it can't be scratched with a finger nail Amanda, it leaves a grey- silver streak on the back of a tile but makes quite a noise doing it.
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Uwe Ludwig May 14, 2012 08:30PM
Did you already check whether it could be Molybdänite? Molybdänite occurs often together with quartz opposed to native silver. I add a picture for comparison.

Uwe Ludwig
open | download - Molybdänit-Schlema.JPG (194.7 KB)
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Heath Barnes May 14, 2012 08:45PM
Uwe no and if ime honest as i write this ime still in the dark as to what the mineral you have shown me actually is but yes i agree it looks very similer ime going to google it now but any more images or imformation would be most welcome.
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George Creighton May 14, 2012 09:00PM
Think Uwe is referring to this mineral " molybdenite " at this location :- http://www.mindat.org/gallery.php?min=2746

Also tend to agree with this suggestion

Regards

Edit,,,, went through all 500+ but could not find the variety/type Uwe alluded too



Edited 1 time(s). Last edit at 05/15/2012 06:45AM by George Creighton.
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Heath Barnes May 14, 2012 09:09PM
Thanks George
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Heath Barnes May 14, 2012 09:57PM
Any more info on this mineral please as usual ive been totaly confused by the google button !
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Uwe Ludwig May 15, 2012 11:05AM
Hello Heath,

google is not the best solution to check minerals. Go to the link: http://www.handbookofmineralogy.org/search.html?p=all.

There you find a complete description of Molybdenite (and of all other minerals).

At the beginning of this thread you wrote about a black soft tarnish. That may be Jordesite which is also a molybdene sulfide.

@George: I found the molybdenite which I showed on the dump of the mine 371. You find the mineral list of this location at Niederschlema, shaft 371. However, this was a relatively rare mineral there.

rgds.
Uwe Ludwig
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George Creighton May 15, 2012 02:44PM
Thanks Uwe found it now thumbs up

Regards george
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Heath Barnes May 15, 2012 08:14PM
Heath Barnes Wrote:
-------------------------------------------------------
> No it can't be scratched with a finger nail
> Amanda, it leaves a grey- silver streak on the
> back of a tile but makes quite a noise doing it.


Appolagies to all it can be scratched with a finger nail i did not look close enough!!!
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Heath Barnes May 15, 2012 08:32PM
Uwe Ludwig Wrote:
-------------------------------------------------------
> Did you already check whether it could be
> Molybdänite? Molybdänite occurs often together
> with quartz opposed to native silver. I add a
> picture for comparison.
>
> Uwe Ludwig


Uwe thanks for the help one thing that ive not managed to find is anything simmiler to the way my example apears to be flowing through the quartz?
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Heath Barnes June 08, 2012 11:11PM
I have had this piece looked at by Roger and he tells me it is not native Silver in Quartz Sorry we had to much to think about today i think its a form of mica with unexplained black easily polished tarnish ?
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Heath Barnes June 15, 2012 10:03PM
I have now looked some of this stuff up and i think it could be black biotite mica, in quartze?
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