Gold vermeil vs gold plated sterling

I am in the process of purchasing electroplating equipment. I
thought I wanted to do a heavy plate of gold over sterling to
produce gold vermeil. I’m concerned about things I have read about
the oxidation and wear of gold vermeil. I get the impression you
have to nickel plate first to prevent these problems. Is there a way
to produce gold vermeil without these problems. Also, how do you
measure the thickness of plating to assure you meet the minimum
requirement?

You don’t have to plate a sterling piece with nickel before applying
gold plating- Having the sterling completely clean and grease free is
critical to laying on a good film of whatever metal you wish the
plating to be.

You have to choose good solvents in that case as an ultrasonic or
steam is not adequate when dealing with a final product and for all
practical purposes-finished,- or all but stone set or some other
non-destructive or abrasive operation as it comes out or the bath.
Some people put a rhodium plating for longevity as opposed to
colouration, over the gold in ordinary ‘gold plating’ but vermeil
implies at least 14 karat (58% gold fineness) over sterling or fine
silver. And to introduce nickel would require that you disclose that
a base metal is in the alloy though it is technically not part of the
sterling alloy! Today vermeil implies a higher karat gold usually 22
or 24kt plated over at least sterling and at a thickness of at least
2.5 microns- it will be soft and thin unless you insure it is
thicker- the kind of equipment you purchase may have the ability to,
say, digitally “dial in” the rate of application of the gold
solution, otherwise you will have to calculate the amount of gold in
the solution and the rate of application as the equipment
manufacturer intends vs the result you wish to achieve making the
necessary adjustments, perhaps initially consulting the manufacturer
for technical assistance in setting it up to accomplish what you
desire the result to be!Using a lower karat gold would require a
thicker plating by law, particularly if exporting the finished
product overseas basically doubling the thickness for each reduction
in standard karat values…(it’s fairly easy math - if you need the
formula for the equation I can send it to you).

Anything plated is going to wear-PERIOD! sealants look like sealants-
I would suggest applying a thicker than standard coating, and
charging appropriately for it. The other alternative is to plate with
rhodium, but then you compromise the vermeil standard. o better not
to offer pieces that will wear faster like rings, that see a lot of
knocking about in a days’ ordinary wear. You could get into all sorts
of “lifetime guarantees” like an annual re-plating for a nominal
charge that allows you to inspect the workpiece for yourself as well
as gets the client into your studio/store, but given a volatile gold
market (artificially inflated or not!) The costs of offering any
guarantee of this nature are inevitably going to rise over the years-
so you would have to price the piece accordingly initially. that
pricing would take some thought and thinking about it also figure the
type of plating you are considering- whether rack or “pen” plating(or
any other method you personally do by hand if the piece is detailed)
as opposed to mass plating or even something like “line” plating most
often used in manufacturing large quantities of pieces that you will
later assemble or even outsource their assembly- I don’t guess that’s
what you are considering though! If I can clarify anything don’t
hesitate to ask Best regards, rer

Vermeil means gold plate over sterling, so “gold” is an unnecessary
modifier. There is no other kind of vermeil than gold over sterling.

Silver can tarnish through a layer of plating if the plating is not
thick enough. Gold electroplate is gas porous in thin layers.

You need to check your own country’s marking laws to see what
thickness of gold is needed over the sterling to be legally marked as
vermeil.

In the US, for instance, to be marked as vermeil the gold plating
must be at least 2.5 microns thick. Also, if there is a layer of
nickel below the gold than that also must be disclosed. If you just
mark or advertise the item as vermeil, the gold layer must be
directly over the sterling.

Here is the relevant section of US law.

Elliot Nesterman

I got my pen plating equipment from Rio Grande, and they told me if
I was going to plate on sterling I do have to plate with nickel
first - otherwise the gold “sinks” into the silver as I understand
it (definitely NOT an expert!). It is not a big deal to plate first
in nickel, then in gold though…

Can’t answer the rest of your questions, sorry.

I love my Midas pen plating system though!

Beth Wicker

You don't have to plate a sterling piece with nickel before
applying gold plating- Having the sterling completely clean and
grease free is critical to laying on a good film of whatever metal
you wish the plating to be. 

My understanding is that the reason nickel plating is used as an
“undercoat” is to provide a barrier between the sterling and the
gold.

It keeps oxides on the sterling from discoloring the gold plate and
it keeps the gold and silver from amalgamating.

As Beth noted gold will diffuse (sink) into the sterling. This will
cause two problems, first the piece will shift color and become
greener in tone as the silver and gold mix, second it will begin to
tarnish. Most makers are ignorant of these issues or just don’t
worry about it. The reason for a nickel flash over the silver is to
prevent diffusion, nickel is a diffusion barrier. As Elliot noted if
you use a barrier of a base metal you must disclose it on the piece.
However if you use palladium plating rather than nickel you do not
have to disclose it as it is not a base metal.

As for measuring the thickness of the plating your best bet is to
hire an analytical lab to do it for you. If you want to purchase the
tools to do it there are a couple of ways it is done.

  1. X-Ray Florescence instruments that are calibrated to measure the
    plating thickness, very expensive machine.

  2. Beta Backscatter, expensive but not as expensive as an XRF
    machine.

  3. Optical metallography where the piece is cut and polished and the
    layer thickness is measured with a precision reticle on a
    microscope. Still thousands of dollars in equipment and training to
    use it but less expensive than the previous two.

  4. Use an analytical balance to weigh before and after plating. The
    least accurate method and requires a very expensive analytical
    balance (scale)

James Binnion
James Binnion Metal Arts

You don't have to plate a sterling piece with nickel before
applying gold plating- Having the sterling completely clean and
grease free is critical to laying on a good film of whatever metal
you wish the plating to be. 

Correction on line 1: should read…“you don’t have to plate a fine
silver piece with nickel…”

Correction on line 1: should read..."you don't have to plate a
fine silver piece with nickel...." 

Yes you do if you want to keep the gold and silver from diffusing
into each other.

There’s a very interestingnew XRF application note concerning
multi-layer coating measurement, available here:
http://www.ganoksin.com/gnkurl/ep825k It outlines new work with
Au/Pd/Ni/Cu and other multi-layer combinations.

Mark Bingham