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Identity HelpNative silver in quartz ?
4th May 2012 21:21 UTCAnonymous User
4th May 2012 21:27 UTCRob Woodside 🌟 Manager
4th May 2012 21:34 UTCAnonymous User
4th May 2012 21:37 UTCRob Woodside 🌟 Manager
4th May 2012 21:42 UTCDon Saathoff Expert
Don
4th May 2012 21:53 UTCMaggie Wilson Expert
4th May 2012 22:02 UTCAnonymous User
4th May 2012 22:59 UTCAnonymous User
5th May 2012 00:30 UTCPaul Brandes 🌟 Manager
5th May 2012 09:12 UTCAnonymous User
-------------------------------------------------------
> 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 ! )
5th May 2012 09:59 UTCAnonymous User
5th May 2012 10:26 UTCUwe Ludwig
Uwe Ludwig
5th May 2012 11:50 UTCClaire Brimson
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
5th May 2012 16:01 UTCRob Woodside 🌟 Manager
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.
5th May 2012 17:53 UTCUwe Ludwig
Uwe Ludwig
5th May 2012 19:19 UTCRob Woodside 🌟 Manager
5th May 2012 20:05 UTCAnonymous User
-------------------------------------------------------
> 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.
5th May 2012 20:16 UTCAnonymous User
-------------------------------------------------------
> 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.
5th May 2012 20:20 UTCAnonymous User
-------------------------------------------------------
> 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
5th May 2012 20:27 UTCRob Woodside 🌟 Manager
5th May 2012 20:29 UTCAnonymous User
-------------------------------------------------------
> 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;;-)
5th May 2012 20:29 UTCAlfredo Petrov Manager
2) Hematite pebble, perhaps?
3) Septarian concretion.
4) Flint.
The latter two are quite nice specimens :)-D
5th May 2012 20:32 UTCAnonymous User
-------------------------------------------------------
> 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 !
5th May 2012 20:32 UTCRob Woodside 🌟 Manager
5th May 2012 20:33 UTCRob Woodside 🌟 Manager
5th May 2012 20:35 UTCAnonymous User
5th May 2012 23:25 UTCAnonymous User
5th May 2012 23:47 UTCAnonymous User
6th May 2012 01:45 UTCDon Saathoff Expert
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.
6th May 2012 08:04 UTCClaire Brimson
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
6th May 2012 14:06 UTCAnonymous User
-------------------------------------------------------
> 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.
6th May 2012 14:24 UTCAnonymous User
-------------------------------------------------------
> 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 !;-)
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
6th May 2012 14:41 UTCAnonymous User
6th May 2012 19:26 UTCRob Woodside 🌟 Manager
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..
6th May 2012 19:43 UTCAnonymous User
6th May 2012 19:46 UTCAnonymous User
-------------------------------------------------------
> 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?
6th May 2012 20:21 UTCAnonymous User
6th May 2012 20:50 UTCRob Woodside 🌟 Manager
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,
6th May 2012 20:54 UTCRob Woodside 🌟 Manager
6th May 2012 21:41 UTCAnonymous User
7th May 2012 00:11 UTCD Mike Reinke
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!
7th May 2012 02:12 UTCJim Bean 🌟
7th May 2012 03:23 UTCRock Currier Expert
7th May 2012 12:32 UTCAnonymous User
-------------------------------------------------------
> 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?
7th May 2012 12:48 UTCAnonymous User
7th May 2012 18:15 UTCClaire Brimson
-------------------------------------------------------
> 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!
7th May 2012 19:58 UTCAnonymous User
7th May 2012 20:09 UTCAnonymous User
-------------------------------------------------------
> 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 ?
7th May 2012 20:31 UTCRob Woodside 🌟 Manager
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.
7th May 2012 21:18 UTCAnonymous User
7th May 2012 21:38 UTCAlfredo Petrov Manager
7th May 2012 22:09 UTCAnonymous User
7th May 2012 23:47 UTCAnonymous User
8th May 2012 00:52 UTCAlfredo Petrov Manager
8th May 2012 04:16 UTCD Mike Reinke
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.
8th May 2012 04:54 UTCStephanie Martin
http://www.mindat.org/forum.php?read,11,250282,page=1
Hope this helps.
regards,
stephanie :-)
8th May 2012 21:22 UTCAnonymous User
12th May 2012 21:00 UTCBecky Coulson 🌟 Expert
Heath, I'm curious about your research in the Cleveland area. What are you researching? Cheers, Becky
12th May 2012 21:35 UTCAnonymous User
12th May 2012 22:16 UTCAnonymous User
14th May 2012 19:31 UTCAmanda Hawkins
14th May 2012 20:50 UTCAnonymous User
14th May 2012 21:30 UTCUwe Ludwig
Uwe Ludwig
14th May 2012 21:45 UTCAnonymous User
14th May 2012 22:00 UTCGeorge Creighton
Also tend to agree with this suggestion
Regards
Edit,,,, went through all 500+ but could not find the variety/type Uwe alluded too
14th May 2012 22:09 UTCAnonymous User
14th May 2012 22:57 UTCAnonymous User
15th May 2012 12:05 UTCUwe Ludwig
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
15th May 2012 15:44 UTCGeorge Creighton
Regards george
15th May 2012 21:14 UTCAnonymous User
-------------------------------------------------------
> 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!!!
15th May 2012 21:32 UTCAnonymous User
-------------------------------------------------------
> 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?
9th Jun 2012 00:11 UTCAnonymous User
15th Jun 2012 23:03 UTCAnonymous User
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Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 19, 2024 02:36:25