Home |
Search |
Today's Posts |
![]() |
|
Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
![]() |
|||
|
|||
![]()
Ignoramus27444 wrote in
: I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". [snip] Can this possibly be gold? Certainly. 14 karat gold is quite susceptible to tarnishing -- it's less than 60% gold, with the other 40% usually being copper. |
#2
![]() |
|||
|
|||
![]()
I've seen and lost wax cast 14K and 10K Yellow and Pink Gold and these
pictures look much more tarnished than I would expect. Alan Black "Murray Peterson" wrote in message ... Ignoramus27444 wrote in : I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". [snip] Can this possibly be gold? Certainly. 14 karat gold is quite susceptible to tarnishing -- it's less than 60% gold, with the other 40% usually being copper. |
#3
![]() |
|||
|
|||
![]()
"Alan Black" wrote in
m: I've seen and lost wax cast 14K and 10K Yellow and Pink Gold and these pictures look much more tarnished than I would expect. I make jewelry as well, and in my experience, it seems to depend on skin chemistry. My wife can't wear any 14k gold -- it turns even blacker than what is seen in the pictures. |
#4
![]() |
|||
|
|||
![]()
Ignoramus27444 wrote in
: In any case, I appreciate your opinion. And that's all it is, since the only way to be sure is to test the piece. Take it to a jeweler and have it tested. |
#5
![]() |
|||
|
|||
![]() "Ignoramus27444" wrote in message ... I asked this question in another newsgroup, but decided to also ask here, since there is a bunch of experts who can probably give some good input. I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". For very high quality scans (including enlarged pictures) of the chain, see http://igor.chudov.com/tmp/gold-chain/ (click on the thumbnail images to enlarge). Can this possibly be gold? I am going to sam's club tonight and will ask their jeweler also. I think that the person who gave me this present got screwed. If you own, or have access to, an accurate digital (or anaolog) scale, then you could do a specific gravity test on the chain. This is not absolutely definitive, but is a damn good indicator. The scale should be 0.01g resolution. The more common 0.1g resolution unit will give less accurate, but still useable results. See http://mendosus.com/sg.html for the method. -- Jeff R. |
#6
![]() |
|||
|
|||
![]() |
#7
![]() |
|||
|
|||
![]()
I took a look at the pictures.
The 14k stamp on the tab appears to be machine done. Now, these ends can be obtained prestamped, but are actually made of 14k. In the pictures, both the chain tip and the clasp are discolored to the same extent as the rest of the chain. Most fakes I've seen have either a poorly stamped mark or are a cheap chain with a 14k tag and clasp. Either this was produced by a highly organized bunch of fakers, or something else is the problem. You haven't been wearing this in a hottub or swimming pool, have you? Paul K. Dickman Ignoramus27444 wrote in message ... I asked this question in another newsgroup, but decided to also ask here, since there is a bunch of experts who can probably give some good input. I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". For very high quality scans (including enlarged pictures) of the chain, see http://igor.chudov.com/tmp/gold-chain/ (click on the thumbnail images to enlarge). Can this possibly be gold? I am going to sam's club tonight and will ask their jeweler also. I think that the person who gave me this present got screwed. -- --------------------------------------------------------------------------- - char*p="char*p=%c%s%c;main(){printf(p,34,p,34);}" ;main(){printf(p,34,p,34); } "It's never too late to have a happy childhood." |
#8
![]() |
|||
|
|||
![]()
Looks like Chlorine tarnish to me. You been swimming with it on?
Ignoramus27444 wrote: I asked this question in another newsgroup, but decided to also ask here, since there is a bunch of experts who can probably give some good input. I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". For very high quality scans (including enlarged pictures) of the chain, see http://igor.chudov.com/tmp/gold-chain/ (click on the thumbnail images to enlarge). Can this possibly be gold? I am going to sam's club tonight and will ask their jeweler also. I think that the person who gave me this present got screwed. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
#9
![]() |
|||
|
|||
![]()
There is a simple way to determine the percentage of gold on a comparison
basis. Typically 10K is 25%,14K is 50%, 18K 75%, 22K 90% gold and the rest is alloying materials mostly of which is copper. The blend of these alloying elements vary nation to nation. Depending on a person's skin's acid content, corrosion can take place. The test you can do is simple. You will need an Arkansas stone, test samples and a small bottle of sulfuric acid. Ideally, you should have a test sample of each known carat weight. Rub each sample, creating a line on the stone, then take your unknown sample and rub a line with that. With a glass rod, collect a drop of acid and deposit the acid on the test lines on the stone. You will then see the lines fade as the acid eats the alloying elements. The 22K sample will hardly change, the 10K sample will virtually dissapear. By comparing your unknown sample, you can readily determine the gold content. Please note that the rubbing of the samples on the Arkansas stone will not damage the samples. Steve "Ignoramus27444" wrote in message ... In article , A.Gent wrote: "Ignoramus27444" wrote in message ... I asked this question in another newsgroup, but decided to also ask here, since there is a bunch of experts who can probably give some good input. I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". For very high quality scans (including enlarged pictures) of the chain, see http://igor.chudov.com/tmp/gold-chain/ (click on the thumbnail images to enlarge). Can this possibly be gold? I am going to sam's club tonight and will ask their jeweler also. I think that the person who gave me this present got screwed. If you own, or have access to, an accurate digital (or anaolog) scale, then you could do a specific gravity test on the chain. This is not absolutely definitive, but is a damn good indicator. The scale should be 0.01g resolution. The more common 0.1g resolution unit will give less accurate, but still useable results. See http://mendosus.com/sg.html for the method. I do not have such a scale, but I really like the method. It is simple and very clever. -- -------------------------------------------------------------------------- -- char*p="char*p=%c%s%c;main(){printf(p,34,p,34);}"; main(){printf(p,34,p,34);} "It's never too late to have a happy childhood." |
#10
![]() |
|||
|
|||
![]() Ignoramus27444 wrote: In article BUMoc.15296$Lm3.2986@lakeread04, Glenn Ashmore wrote: Looks like Chlorine tarnish to me. You been swimming with it on? Is there any way to clean chlorine tarnish? I believe I would take it to a jeweler and have him use his ultrasonic cleaner. Besides tarnishing, chlorine reacts with gold similar to crevasse corrosion in stainless . It weakens clasps and prongs. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
#11
![]() |
|||
|
|||
![]()
A lot of stuff is 14K "filled" which is to say "plated" If this was plated and wore off, then the base metal is most likely
brass or copper. R. Wink On 13 May 2004 13:50:29 GMT, Ignoramus27444 wrote: I asked this question in another newsgroup, but decided to also ask here, since there is a bunch of experts who can probably give some good input. I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". For very high quality scans (including enlarged pictures) of the chain, see http://igor.chudov.com/tmp/gold-chain/ (click on the thumbnail images to enlarge). Can this possibly be gold? I am going to sam's club tonight and will ask their jeweler also. I think that the person who gave me this present got screwed. |
#12
![]() |
|||
|
|||
![]()
Ignoramus27444 wrote:
Is there any way to clean chlorine tarnish? http://www.metalworking.com/dropbox/_1999_retired_files/E-CLEAN.TXT http://www.metalworking.com/dropbox/_1999_retired_files/E-CLEAN2.TXT Ted |
#13
![]() |
|||
|
|||
![]()
On Thu, 13 May 2004 17:19:58 GMT, R. Wink
wrote: A lot of stuff is 14K "filled" which is to say "plated" If this was plated and wore off, then the base metal is most likely brass or copper. R. Wink Goldfilled is not goldplated. cf: McCreight's Complete Metalsmith book , et al. |
#14
![]() |
|||
|
|||
![]() wrote in message news ![]() On Thu, 13 May 2004 17:19:58 GMT, R. Wink wrote: A lot of stuff is 14K "filled" which is to say "plated" If this was plated and wore off, then the base metal is most likely brass or copper. R. Wink Goldfilled is not goldplated. cf: McCreight's Complete Metalsmith book , et al. The words "gold filled" are somewhat a misnomer, although well accepted in the jewelry industry. What would be more appropriate would be filled gold, meaning that the outer shell is made of gold alloy, which has been affixed to base metal, either one side or both, then the items fabricated. The stock is often further processed after the gold layer has been applied, including rolling to specific thickness before further fabrication. Gold filled jewelry will usually specify its content with a fraction and the karat fineness. Old eyeglass frames were so marked (assuming they were gold frames), with a common marking of 1/10 12K GF, for example. That's telling you that 1/10 of the mass is 12K gold, or the item was fabricated with an overall pure gold content of 5%. In gold, 24 K(arat) is pure, thus one K =4.1666% gold. Marking regulations allowed for deviations according to manufacturing procedures, so the items made were usually a half karat lower than the marking, which was perfectly legal at the time they were made. If the chain in question is made from karat gold, not gold filled or plated, a drop of nitric acid would slightly discolor the area where the acid was applied, turning it a brown color after standing for a few moments. . If there is a greenish reaction, one that takes place very rapidly, that's a sure sign that the chain is either plated or gold filled. A chain that has been worn some time will usually have enough wear to expose the base metal, which is what the nitric will be dissolving. Another test for the chain to determine if it is karat gold or gold filled would be to soak the chain in ammonia over night. Gold filled chains slowly dissolve away at the core, turning the cleaning solution greenish blue in the process. Karat gold will tolerate cleaning that way endlessly, so it's a good way to keep jewelry clean. One must be careful to not soak pearls or cheap jewelry, however. Only high quality karat gold jewelry should be so cleaned. Harold |
#15
![]() |
|||
|
|||
![]() "Ignoramus27444" wrote in message ... So yer a professional troll, eh ??? I asked this question in another newsgroup, but decided to also ask FYI: Its a black thing and probly has six or more wires on it, at least four are gonna be fairly heavy gage, and you gotta make damned sure ya get all the wires back in the right place, else POOFT!!! I still say there was probly just a bug stuck in it..... BTW: Hows yer foot doing ??? G -- SVL |
#16
![]() |
|||
|
|||
![]()
On Thu, 13 May 2004 18:03:26 +0200, "Steve Lusardi"
wrote: There is a simple way to determine the percentage of gold on a comparison basis. Typically 10K is 25%,14K is 50%, 18K 75%, 22K 90% gold and the rest is alloying materials mostly of which is copper. The blend of these alloying elements vary nation to nation. Depending on a person's skin's acid content, corrosion can take place. The test you can do is simple. You will need an Arkansas stone, test samples and a small bottle of sulfuric acid. Ideally, you should have a test sample of each known carat weight. Rub each sample, creating a line on the stone, then take your unknown sample and rub a line with that. With a glass rod, collect a drop of acid and deposit the acid on the test lines on the stone. You will then see the lines fade as the acid eats the alloying elements. The 22K sample will hardly change, the 10K sample will virtually dissapear. By comparing your unknown sample, you can readily determine the gold content. Please note that the rubbing of the samples on the Arkansas stone will not damage the samples. Steve This is the most common test in pawn shops btw. Gunner "A vote for Kerry is a de facto vote for bin Laden." Strider |
#17
![]() |
|||
|
|||
![]()
On Thu, 13 May 2004 17:19:58 GMT, R. Wink wrote:
A lot of stuff is 14K "filled" which is to say "plated" If this was plated and wore off, then the base metal is most likely brass or copper. R. Wink A lot of it is also plated silver, oddly enough. From my days working in a pawn shop, I was told by a guy who really knows the business, that a lot of heavy silver jewelry was made, then when the price of silver went into the crapper, they had it gold plated. Gives a feeling of heavyness, and the scam part was to say it was 100% precious metal. He cut a link in half and showed me the silver center. (he was a superior jewelry repair guy too) Gunner On 13 May 2004 13:50:29 GMT, Ignoramus27444 wrote: I asked this question in another newsgroup, but decided to also ask here, since there is a bunch of experts who can probably give some good input. I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". For very high quality scans (including enlarged pictures) of the chain, see http://igor.chudov.com/tmp/gold-chain/ (click on the thumbnail images to enlarge). Can this possibly be gold? I am going to sam's club tonight and will ask their jeweler also. I think that the person who gave me this present got screwed. "A vote for Kerry is a de facto vote for bin Laden." Strider |
#18
![]() |
|||
|
|||
![]() "Steve Lusardi" wrote in message ... There is a simple way to determine the percentage of gold on a comparison basis. Typically 10K is 25%,14K is 50%, 18K 75%, 22K 90% gold and the rest is alloying materials mostly of which is copper. snip-------- Close, but no cigar. Considering karat gold is defined as 24K=100% gold content, 10K is 41.6% gold (by weight), 12K is 50% content, 14K is 58.33% content, 22K is 91.66% content. You had it right on the 18K. In the US, it is illegal to mark gold under 10K, but that is not true in other countries. Regards the alloying agent, while copper tends to be the major alloying element, the color of the gold dictates what is used, and in what proportions. Yellow gold is comprised of silver and copper, generally with a trace of a sacrificial element to keep the base metal from oxidizing, often times just zinc. White gold has no copper at all, but contains nickel instead. Green gold is primarily silver and gold. Blue comes from the addition of iron. Harold |
#19
![]() |
|||
|
|||
![]()
Harold & Susan Vordos wrote:
(snip) dictates what is used, and in what proportions. Yellow gold is comprised of silver and copper, generally with a trace of a sacrificial element to keep the base metal from oxidizing, often times just zinc. White gold has no copper at all, but contains nickel instead. Green gold is primarily silver and gold. Blue comes from the addition of iron. Harold And if I remember right, aluminum gives you purple, but it is too brittle to work and can only be cast. Todd |
#20
![]() |
|||
|
|||
![]() "Todd Rich" wrote in message ... Harold & Susan Vordos wrote: (snip) dictates what is used, and in what proportions. Yellow gold is comprised of silver and copper, generally with a trace of a sacrificial element to keep the base metal from oxidizing, often times just zinc. White gold has no copper at all, but contains nickel instead. Green gold is primarily silver and gold. Blue comes from the addition of iron. Harold And if I remember right, aluminum gives you purple, but it is too brittle to work and can only be cast. Todd Yeah, lots of other colors can be created beyond those we've mentioned, a list of which I have in my possession, a leftover from my precious metal refining days. As you stated, some colors are created at the expense of loss of ductility. You can cast the alloy, but it can't be worked beyond cleaning and polishing. Do you wonder how many people actually understand why gold comes in different colors? My experience as a refiner was that almost no one understands gold unless they work with it, and even then many don't have a clue. It was a fun hobby, and then a great way to make a living, but like any hobby that turns into a job, that's what it was in the end, and it was a happy day when I sold by refining business and retired. I'd had enough "fun" by then. Harold |
#21
![]() |
|||
|
|||
![]()
Ignoramus27444 wrote:
In article , Murray Peterson wrote: Ignoramus27444 wrote in : I received a "gold chain" as a birthday present, two months ago. Since then, the chain has discolored in ways that made me suspect that it is not real gold. It is stamped "14K Italy". [snip] Can this possibly be gold? Certainly. 14 karat gold is quite susceptible to tarnishing -- it's less than 60% gold, with the other 40% usually being copper. Well, I have a 14k wedding ring, and id did not tarnish like that when I wore it continuously. I do not wear it now because I lost weight and the ring falls off. In any case, I appreciate your opinion. Right - but it is solid 14K like mine (in white gold). Plated 14K can be very thin and if the body is acidic it can strip the copper and the gold is dust by the leaching. Martin -- Martin Eastburn, Barbara Eastburn @ home at Lion's Lair with our computer NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder |
#22
![]() |
|||
|
|||
![]()
Todd Rich wrote:
Harold & Susan Vordos wrote: (snip) dictates what is used, and in what proportions. Yellow gold is comprised of silver and copper, generally with a trace of a sacrificial element to keep the base metal from oxidizing, often times just zinc. White gold has no copper at all, but contains nickel instead. Green gold is primarily silver and gold. Blue comes from the addition of iron. Harold And if I remember right, aluminum gives you purple, but it is too brittle to work and can only be cast. Todd Just as long as it isn't an aluminum pad and a gold wire purple plague. That is purple. Martin -- Martin Eastburn, Barbara Eastburn @ home at Lion's Lair with our computer NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Chain tensioner ideas | Metalworking | |||
OT - Property Chain WTF??? | UK diy | |||
Gold and Silver | Metalworking | |||
Gold Coloured Shower question | UK diy |