Sterling silver. The low down and info goes here.

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Smitty37

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wowsers.. that was alot of reading. are you guys intentionally trying to give yourself a headache here?

If the point of all of this is to see if kits are being fraudulently advertised, then it sounds like you've all worked that one out. As one post correctly said, its marketing. People presume sterling just means of really high excellent shiny quality and never get too drawn in with the technicalities of it. It's only the advanced turners who would even contemplate questioning this.

Ed, what you're referring to is chromate film, not resin :wink: which stops tarnishing.

There are general requirements for all types of surface engineering. With Silver, falling under Federal specification QQ-S-365D (Because I know you all love factual codes :biggrin: )

Matte (type I)
Semibright (type II)
bright (type (III)
and with chromate filme (grade A)
Without film (Grade B)

The minimum thickness of 13μm

Then there's all the types which begin with AMS, which is used in aerospace which is obviously of a higher standard and stricter tolerances

Then there's ISO standards.



With regards to the plating process itself its almost exclusively done in a cyanide solution. They've exhaustively tried less toxic alternatives but struggle to match the overall results.

Firstly, it's not just a metal in these plating solutions. they're recipes to give the desired effect. I would put money on that these "sterling kits" simply contain a carbonate to aid conductivity and act as a brightener to make them extra shiny. (I will tell you all about carbonates and trisodium phosphate's in a few months ;) People who own metal lathes will love this stuff - don't ask, it's all secret for now :tongue: )

A typical recipe commercially used for plating silver decorative parts is

Silver as KAg(CN)2 g/L 15-40
Potassium Cyanide g/L 12-120
Potassium Carbonate g/L 15


if you think that's bad... just wait until you dive into gold and "chrome" ;)

half the time chrome isn't chrome
and ive seen pinkish coloured gold labelled as 24ct which is impossible. It's the cobalt hardener they add which turns it to a pink hue and cannot be classified as 24ct as a result of it. Also not very cheap solution either. costs me £290 per litre, for 6g/L


Smitty, you're in the right ball park with the zinc plate. It stops the copper based alloys from leaching through the silver plating.
I had heard about a small amount of colbalt being added to increase wearability but hadn't heard about the effect on color.

One vendor selling Sterling kits has said the kit parts are .925 Silver then are silver plated to stop tarnish.... I am under the impression they are stamped somewhere on the kit.
 

BradG

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Incase anyone's interested about gold plating:

The trouble with a gold bath is that it's starved to begin with, which makes it very difficult to manage. It's starved because of the cost of gold naturally

In comparison:

A chrome bath contains over 240g of metal per litre
Nickel and silver typically contain 37g per litre
Acid copper around 67g per litre

Gold on the other hand rarely contains more than a troy ounce per gallon (8.2g/L)

Gold used for striking and decorative touches can contain as little as 0.4 g/L

So it goes to show gold plating isn;t just gold plating. The quality and thickness of the plate will be determined by many factors, but ultimately will be limited to the gold concentration of the electrolyte itself.

Here's a snippet from one of my books
With a starved solution, every control parameter in the plating process
becomes more critical. Gold concentration, electrolyte concentration, pH, impurity level, and additive level must all be
monitored and controlled. Temperature, current density, agitation, and the current efficiency must be accurately known
and controlled beyond the degree necessary for copper, nickel, or even silver plating. If any factor changes, even 2 to 3%,
the cathode gold deposition efficiency changes. If the efficiency decreases, items being plated under standard conditions
will be underplated and the specified thickness will not be attained. Similarly, if the cathode efficiency increases, the plate
will be too thick and result in increased cost because of using excess gold.

The engineer and plater of gold must tread the narrow line between not depositing enough gold and giving away too much
gold. In addition, those concerned with gold plating must not only keep the chemistry of the process and the peculiarities
of electrodeposition in mind, as do other platers, but also be aware of the market price of gold. The plater must be an
economist in order to realize when the operating conditions of the solution should be altered or the entire process changed
to reflect the changes in the price of gold. Economics also determines the total consumption of gold. In the recent past,
when the price of gold vaulted above $500 per troy ounce, many electronics companies replaced some of the total
thickness of gold with undercoats of palladium or palladium-nickel alloys. Others abandoned gold completely. Economics
is a more important factor in the plating and metallurgy of gold than in the plating of nonprecious metals.

So, how do platers respond? Well, if I were to plate something in 0.4g/L the work is going to look pretty dull and poor to say the least because of how thin I would be doing the plating.. but what if I chrome plated it first and then gave it a thin coating of gold? The shine of the chrome will show through the thin layer of gold "appearing" to be really shiny gold. Take a look at the attached pens for comparison. both have been chrome plated (actually bright nickel - not chrome.. another industry lie... but could you tell the difference with an untrained eye?), and one has been brush plated with gold.. so a very thin coating, but the lustrous shine bursts through because of the chrome effect beneath. The third pen, which is etched has just been gold plated with no chrome underneath... see how dull it is?

Going on from there, different types of gold plating

FLASH PLATING - short process, generally 5 to 30 seconds and the deposit is around 0.05 to 0.1 μm
24ct
Gold 2g/L

18ct
Gold 1.6g/L
Nickel 0.15-1.5g/L

Hamilton
Gold 1.25g/L
Nickel 0.3g/L
Copper 1.5g/L

White
0.4 g/L
Nickel 1.1g/L

Rose
Gold 4.1 g/L
sodium hydroxide 15g/L
sodium carbonate 30g/L


As we can see, the gold content of Rose gold plating is alot higher than the others with 24ct coming in second.


These types of plating CANNOT be marketed as a gold electroplate as then it would require a thickness of at least 0.175μm.

If marketed as heavy gold, then 2.5μm


The trouble here, is because all of these values are so low compared to other metal plates, its very hard to maintain the balance of all of these metals in the gold bath. A slight drift in ph or electrolyte concentration of macrometals if you will, will give varied results including colour. not good if you;re looking for repeatability.
 

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edstreet

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No longer confused....
How do you account for things like Ti gold and black Ti with color shifting over time? These exhibit changes that we do not see in plated tooling like drill bits etc.

Also coatings like 'gunmetal' seems to be grossly misleading and one huge marketing ploy. I lump this one in with "surgical stainless" or the "jewelry grade", "food grade", "restaurant grade" labeling. So what exactly is 'gunmetal' I know what it is NOT, and that is parkerizing.
 

BradG

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How do you account for things like Ti gold and black Ti with color shifting over time? These exhibit changes that we do not see in plated tooling like drill bits etc.

Also coatings like 'gunmetal' seems to be grossly misleading and one huge marketing ploy. I lump this one in with "surgical stainless" or the "jewelry grade", "food grade", "restaurant grade" labeling. So what exactly is 'gunmetal' I know what it is NOT, and that is parkerizing.
colour shifting can be caused by leaching of the other base metals which are plated beneath, such as what Smitty brushed upon by plating with nickel before your final plate. other variables which could cause the colour to shift is by what the plating actually is as it oxidises.

All of these plates will be done to a decorative level, whereas the plating on toolbits will be alot thicker, and alot stronger, with other alloys mixed in to give it the strength required.

Gunmetal is a mixture of either tin & nickel or cobalt, or zinc which just gives varying colours from dark blues to greys depending on how much of each is in the electrolyte. lots of recipes available for it in different formulations

all of these terms in my opinion, just describe the colour of the plating and do not reflect what the plating actually is.

Black Chrome for instance. looks smart as.. It's just a thin layer of Tin or black nickel plated over chrome. so you get that shiny black look.
 

Smitty37

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How do you account for things like Ti gold and black Ti with color shifting over time? These exhibit changes that we do not see in plated tooling like drill bits etc.

Also coatings like 'gunmetal' seems to be grossly misleading and one huge marketing ploy. I lump this one in with "surgical stainless" or the "jewelry grade", "food grade", "restaurant grade" labeling. So what exactly is 'gunmetal' I know what it is NOT, and that is parkerizing.
Ed, Titanium Gold can legally be listed as 24K gold because the tiny amout of Titanium in it isn't enough to require a lower carat marking.

Gold Tn that commonly used in pen kits refers to the color - it has no Gold metal in it.

What would you call "gunmetal" kits Ed? One of the definitions of gunmetal is "a dark blue-brown gray color" The gunmetal metal, by definition, is a form of bronze.
 

edstreet

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No longer confused....
all of these terms in my opinion, just describe the colour of the plating and do not reflect what the plating actually is.
This would certainly make sense with the testing that I have done. Well the results anyways, esp with the 'platinum' testing (resulted in 0 platinum present)

So on the entire 'titanium' line of plating it would certainly be possible to have no titanium in it correct?

From this I am wondering if it would be advantageous to say there is no gold in gold, no silver in silver, no rhodium in rhodium, no titanium in titanium, no chrome in chrome.
 

Smitty37

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all of these terms in my opinion, just describe the colour of the plating and do not reflect what the plating actually is.
This would certainly make sense with the testing that I have done. Well the results anyways, esp with the 'platinum' testing (resulted in 0 platinum present)

So on the entire 'titanium' line of plating it would certainly be possible to have no titanium in it correct?

From this I am wondering if it would be advantageous to say there is no gold in gold, no silver in silver, no rhodium in rhodium, no titanium in titanium, no chrome in chrome.
Advantageous to who? Since for the most part, that isn't exactly true either. What has changed in the last 5 years is the method of applying plating to a base metal. No one said there is no Gold in gold plating....just that there is not much gold in the solution used - what is deposited is gold.

btw the Titanium nitride and Black Titanium platings do contain titanium.
 

BradG

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gold,silver are likely to be just that. how much of it however is debatable.

Different metals I know of which can be plated are these. Ti is not even on the list which leaves me to assume all of those platings are things what just look like what you would expect if it was infact plated in ti.

Chrome
Nickel
Iron
Cadmium
Zinc
Indium
Tin
Lead
Silver
Gold
Platinum Group (including Rhodium)
Copper


The crux of it to me is that all plating is quite frankly that.. plating. if you want something special, then get a solid piece. if you want something what looks the part but infact costs bugger all, then plating wins. I would certainly take all of it with a pinch of salt, and would more focus on how good of a plating the manufacturer offers, rather than what it actually is. Smitty mentioned his chap plates to 20μm which is good considering the requirement is only 13μm. This shows they make a better quality component compared to someone which is just meeting the industry standard, obviously only comparing thickness alone. many other factors need to be checked too to determine who is the better plater, but that would be a hell of alot easier to analyse than trying to figure out if it is infact Rhodium.
 

edstreet

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No longer confused....
Brad,

I for one would like to thank you for helping out in this topic as for years I have been asking some of these questions; as have others. What little information is out there is not easily obtainable and having seen much marketing hype (I am not going there) that has done nothing but irritate me greatly. You have certainly provided very valuable information.

With all the claims floating around no one has even brought up standards and to my knowledge no vendor list standards or even what the product adheres to.
 

Smitty37

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gold,silver are likely to be just that. how much of it however is debatable.

Different metals I know of which can be plated are these. Ti is not even on the list which leaves me to assume all of those platings are things what just look like what you would expect if it was infact plated in ti.

Chrome
Nickel
Iron
Cadmium
Zinc
Indium
Tin
Lead
Silver
Gold
Platinum Group (including Rhodium)
Copper


The crux of it to me is that all plating is quite frankly that.. plating. if you want something special, then get a solid piece. if you want something what looks the part but infact costs bugger all, then plating wins. I would certainly take all of it with a pinch of salt, and would more focus on how good of a plating the manufacturer offers, rather than what it actually is. Smitty mentioned his chap plates to 20μm which is good considering the requirement is only 13μm. This shows they make a better quality component compared to someone which is just meeting the industry standard, obviously only comparing thickness alone. many other factors need to be checked too to determine who is the better plater, but that would be a hell of alot easier to analyse than trying to figure out if it is infact Rhodium.
I think Titanium nitride and Black Titanium are thought of as ceramics rather than metals. What ever the case I think they can be plated - Titanium Nitride plated drill bits have been available for years. I think the Black Titanium is Titanium Dioxide and is used a lot in making Titanium jewelry - black Titanium rings are common, Walmart even carry's them.

In my opinion, a lot of the confusion here is a matter of semantics. When I first started, most of the platers were electroplating in a bath of liquid and the big argument was over "rack" plating or "tumble" plating....now there are very few platings, if any, done that method, most are done with some sort of a vapor process and there seem to be a lot of factors figureing into the process have changed because of that. I think the end result though must be nearly the same or the whole jewelry industry would be in deep yogart.
 

BradG

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I think Titanium nitride and Black Titanium are thought of as ceramics rather than metals. What ever the case I think they can be plated - Titanium Nitride plated drill bits have been available for years. I think the Black Titanium is Titanium Dioxide and is used a lot in making Titanium jewelry - black Titanium rings are common, Walmart even carry's them.
Indeedy, its an oxide layer rather than a plating from the little googling I just done.

In my opinion, a lot of the confusion here is a matter of semantics. When I first started, most of the platers were electroplating in a bath of liquid and the big argument was over "rack" plating or "tumble" plating....now there are very few platings, if any, done that method, most are done with some sort of a vapor process and there seem to be a lot of factors figureing into the process have changed because of that. I think the end result though must be nearly the same or the whole jewelry industry would be in deep yogart.

I think they've just changed again after banning Fluro's. Back to tank it goes. (and sprung Ti rack for me every time :wink: )

The thing is I don't think we can compare the jewellery market to pen components. Jewellery will be plated to a completely different standard than decorative items. Unless someone is pitching extremely high quality pen components. Even if that was the case... I would like to see the plating data sheets before I would purchase any.
 

Smitty37

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I think Titanium nitride and Black Titanium are thought of as ceramics rather than metals. What ever the case I think they can be plated - Titanium Nitride plated drill bits have been available for years. I think the Black Titanium is Titanium Dioxide and is used a lot in making Titanium jewelry - black Titanium rings are common, Walmart even carry's them.
Indeedy, its an oxide layer rather than a plating from the little googling I just done.

In my opinion, a lot of the confusion here is a matter of semantics. When I first started, most of the platers were electroplating in a bath of liquid and the big argument was over "rack" plating or "tumble" plating....now there are very few platings, if any, done that method, most are done with some sort of a vapor process and there seem to be a lot of factors figureing into the process have changed because of that. I think the end result though must be nearly the same or the whole jewelry industry would be in deep yogart.

I think they've just changed again after banning Fluro's. Back to tank it goes. (and sprung Ti rack for me every time :wink: )

The thing is I don't think we can compare the jewellery market to pen components. Jewellery will be plated to a completely different standard than decorative items. Unless someone is pitching extremely high quality pen components. Even if that was the case... I would like to see the plating data sheets before I would purchase any.
You are probably right about that. I think we think in terms of jewelry because of the precious metals. This thread started as a discussion of Sterling Silver marking...
 

Smitty37

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This is called bait and switch.
What is called bait-and-switch? "this" is not very specific.

BTW the term is "bait-and-switch" and it means: the action (generally illegal) of advertising goods that are an apparent bargain, with the intention of substituting inferior or more expensive goods. Which in my opinion doesn't even apply here.
 
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edstreet

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No longer confused....
Just an update. I have located a lab that will be doing testing for me on this project. We are currently in the planning phase to ensure good conclusive results and valid data.
 
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