hard to work
with. Working with platinum is not difficult.
It requires a different approach with re-
spect to most traditional goldsmithing
techniques, and it will force you to break
some of your habits around the work
bench.
The properties of platinum are unique and
so are some of the techniques it requires.
So lets first take a look at some of the
basic principles and note whats different
and whats important. This observation will
inevitably lead us to discuss the use of
techniques and tools and consequently
move forward to the finer points and
treasured tricks of working with platinum at
the work bench.
THE BASICS:
Bench cleanliness
It cant be stressed enough that cleanli-
ness is the law and foremost rule to live
by when processing platinum. Platinum is
easily contaminated with almost anything
that you use around your work bench and
jewelry shop. Once contaminated, plati-
num can only be reclaimed through costly
refining.
Think of it as a royal metal that requires
white glove treatment. Understanding the
platinum etiquette will reward you with
quick turn-around-time, happy customers
and impressive profit margins. Violating
these rules guarantees lost time, high
refining cost and frustration beyond belief.
If the limitation of space in your work shop
doesnt permit separate platinum-only
benches, clean your work bench and
drawer thoroughly before starting your
work on the platinum piece. Remove all
tools that you use on gold and silver from
the surface of the bench and replace them
with your set of platinum-only tools. This
procedure eliminates the possibility of
accidental contamination. Switch to a
platinum-only bench-pin and attach your © Platinum Guild International USA 2000 All Rights Reserved
2
V6N6
(platinum-only) bees-wax to it. Line your
drawer with a sheet of paper so that your
filings and sweeps are easy to move to
your individually-labeled platinum scrap
bins.
Be cautious when using shop tools like
draw plates, rolling mill or polishing motor,
as each of these work stations represent a
potential risk of contamination,
Polishing:
Drawing:
Be sure that the draw plate is free of
residue from previous operations and has
a polished surface. Steel plates are not
recommended. Tungsten-carbide,
corundum or diamond tools are called for
to ensure a precise cross-section of your
wire or tubing.
Cross-contamination from gold and silver
particles can be avoided by using spe-
cially marked wheels and attachments.
Therefore, one set of brushes, felts,
buffing wheels and emery wheels should
be dedicated for platinum use. Mark your
platinum polishing tools distinctively in a
bright color for example, and keep them in
zip bags or plastic containers with lids.
Store the polishing compounds with the
wheels to reduce the risk of mix-ups.
Clean the polishing station before and
after you polish platinum. This way you
eliminate the risk of cross-contamination
through polishing dust. Change emery
papers and dress buffing wheels often,
since platinum will charge papers and © Platinum Guild International USA 2000 All Rights Reserved
3
V6N6
buff, causing scratches that interfere with
your polishing efforts.
Rolling:
Prior to any platinum rolling operation, clean
the rollers with alcohol. After each rolling
step and before annealing, the platinum
piece should always be treated in a 10%
nitric acid solution to prevent any possible
damage by non-ferrous impurities. A bath of
sodium sulfide acid before heating and
melting, followed by pickling, will remove
any ferrous metal contaminants from the
surface.
The right alloy
There are a variety of platinum alloy
combinations that find use around the
world. Each particular one has been
composed by metallurgists and metal
experts because it has certain properties
that make it particularly suitable when
being used to perform a specific task.
Some alloys are great for castings, others
are ideal for wrought materials, and some
have desirable characteristics to be
applied for settings or chain making (see
chart, Figure 1). So, before you get
started, take some time to analyze which
production steps your design will require
and based on those findings, choose the
alloy that will accommodate your needs
best. The alloy you choose for your design
will impact your manufacturing process
and the wear on your tools. Sometimes,
deciding for one alloy alone is not an
option. Depending on the complexity of © Platinum Guild International USA 2000 All Rights Reserved
4
V6N6
your piece, it might be necessary to
produce individual components from
different alloys, and then assemble them
to one jewelry piece.
Platinums unique properties offer design
opportunities that other precious metals
cant provide. Use these special charac-
teristics to your advantage and create
distinctive platinum designs. Platinum will
maintain its structural strength in thin
sections and cross-sections, and its
resistance to shearing and buckling
makes it the metal of choice for filigree
jewelry and for prong settings.
Finally, in choosing which alloy to use,
consider if you want to export your plati-
num design to foreign countries. If so,
familiarize yourself with the Hallmarking
Regulations in those countries. In Europe,
for instance, there is an uniform standard
of a 950 platinum content. If you produce
900/100 platinum jewelry for the domestic
market, you need to increase the platinum
content in order to be able to export your
products to Europe. Also be aware of the
different marking requirements (e.g. PT
versus PLAT) which differ from country to
country.
Plan your design
In stead of working with one large platinum
casting, try to break the piece down to
smaller individual components, as it is
much easier to get good casting results
for small pieces. Wall thickness is an
important factor when working with plati-
num castings; try to stay under 2mm
cross sections. Plan your brazing seams
and joining sections such that they are
hidden, and not subject to the most
attention. When combining gold and
platinum, use interlocking joining seg-
ments to avoid trouble during assembly.
Assemble and finish the platinum compo-
nents completely before joining them with
karat gold segments. Determine where to
expect stress/
tension, and remember to stress relief the
piece, or the stress can tear your piece
apart. Know the specific properties of the
metals that you are working with, including
the melting ranges of your solders.
Keep the specific gravity of platinum in
mind! Dont design pieces that are too
large, too heavy or too expensive to ever
be sold.
Use welding techniques over brazing
whenever the piece allows. Work with the © Platinum Guild International USA 2000 All Rights Reserved
5
V6N6
highest melting range solder (brazing filler)
that you are comfortable with, and work
from high temperature to low temperature
solders. If a piece is very complex, make a
1,2,3-list of the steps involved. Chances
are that you can catch an error on paper
before you actually commit it in 3-D. (Time
spent = money saved).
Choose wire prongs over cast prongs as
these are less likely to be brittle and have
a better surface quality. Polish the settings
completely before you set stones, and only
start setting after all high temperature work
has taken place.
Switching gears
If your workshop space allows it, have one
bench strictly designated for work with
platinum. This sacrifice in space will
reward you with time-savings when
changing between metals. If you have your
platinum-only tools at your platinum-only
work station, there is little to 110 risk of
accidentally grabbing the wrong file or
emery paper.
Switching physically from the gold bench
to the platinum bench will also help you
focus on switching gears between the
different manufacturing techniques that the
properties of the metals dictate. Some of
the most striking differences are: the need
to wear welding glasses when welding or
brazing; the use of highly polished, clean
cutting tools in combination with generous
lubrication; and the reduced cutting angle
when sawing, drilling or engraving.
Appropriate Tools
Every piece of platinum jewelry is only as
good as the worst tool that was used to
produce it. If the wrong torch, crucible, © Platinum Guild International USA 2000 All Rights Reserved
6
V6N6
soldering pad or polishing wheel is used,
failure is certain.
Utilizing the right tool is important since
this metal requires special tools which can
withstand the higher brazing and welding
temperatures. As a rule of thumb, its safe
to say that a steel-tool should not be used
within half an inch of a torch flame (in the
red-heat stage). This includes tweezers,
soldering picks, and binding wires. The
use of tungsten tools instead is recom-
mended. You can make your own tungsten
tools by using tungsten wire (available at
welding supply stores) which you can
attach to wooden handles for soldering
picks, or which you can solder to other tool
components for a variety of applications.
Also, during all high temperature proce-
dures, welding glasses must be worn to
protect the eyes from the intense glare
that would otherwise cause permanent
eye damage. Depending on the in