Back to Ganoksin | FAQ | Contact

18K white gold casting porosity


#1

hi everyone.

Does anyone casts 18k white gold? What are the alloys used? At
what temperature is it cast? I have a vaccum casting machine and
I use 4" * 4" cylinders.

Thanks for the help.
FADY SAWAYA.
@Artemis


#2

hi fady, 18k w can be very touchy. i havent’ cast it often at all
but have talked with my metal supplier after my casting didn’t
turn out so well. better results were obtained after i spoke to
them.

most white gold alloy is made white with nickel or palladium.
white gold palladium alloys are very soft and are easy to move
with a graver. this alloy is primarily used for setting pave and
more recently used in prongs that you can buy. it has
’platinum like’ qualities and wears pretty well.casting it does
not require borax or flux when casting. you might want use a
platinum crucible (fused silicate? i forget) the flask temp
should be about one thousand degrees below the melting point of
the metal ( according to my metal supplier this is a general rule
of thumb) at the time when the metal enters the flask. an old
friend told me a flask cools about a hundred degrees a minute but
obviously this completely subjective to lot of different factors.

18k w alloyed with nickel has almost all nickel in the alloy with a
little copper. i’m sorry this answer is so long winded. do you know
what type of alloy you have? if you do the best thing is to talk to
metal supply technicians @ hoover & strong or david fell. they can
better zero in on your particular situation than i.

with the 18k nickel i took the flask out of the kiln @ 1250 with the
metal already melted ( by an assistant). that worked.

by the way, i liked your marlin rendering!
good luck!
geo fox
hi everyone.

Does anyone casts 18k white gold? What are the alloys used? At
what temperature is it cast? I have a vaccum casting machine and I
use 4" * 4" cylinders.

Thanks for the help.
FADY SAWAYA.
ARTEMIS@inco.com.lb


#3

18k w alloyed with nickel has almost all nickel in the alloy

Whoever invented this stuff never had to size an 18kw ring. It
is a really bad alloy and I cringe when anything with that
stamp comes across my bench. For those of you who are
unfamilliar with this mutation of precious metal, 18k white gold
does not bend, it breaks, most of the time. It’s the copper in
14k white that makes it somewhat easy to work with and it’s
missing in the 18k. Nickel does not form a consistent molecular
bond with gold causing all sorts of problems ( I use palladium
white gold from Hoover & Strong). For the person who was asking
about casting in it… if it was requested by a customer…just
say NO! Let’s rid the world of this cruel joke to goldsmiths one
and for all!


#4

I’d really like to find a casting company that is casting
palladium white gold alloys at a reasonable price…

Richard D. Hamilton

Fabricated 14k, 18k, and platinum Jewelry
wax carving, modelmaking, jewelry photography

http://www.rick-hamilton.com
@rick_hamilton


#5

Hi,

It is expensive, but try alloying the white gold with platinum.
Palladium is harder than hell, and besides it has an
inconsistant grain structure. I use palladium/gold/silver alloy
all the time in dentistry and it is a HARD.

Skip

                                  Skip Meister
                                NRA Endowment and
                                   Instructor
                                @Skip_Meister
                                05/21/9704:57:50

#6

Hi to Jefferey Everett, Geo Fox and Wendy Newman,

Thank you all for answering.

Jefferey suggested I would first melt the 24k gold with this
"italian mix" and cast it into an ingot. then remelt it and cast
it into the flask wich temp would be 1100 deg. F. I did all that
but still got BIG porosities. When remelting the white gold, I
could feel the metal hard to liquify. Wich lead me to increase
the heat of the torch. Maybe I shouldn’t do that. I should rather
control my reflexes and cast the metal as soon as it liquify, and
not “push” and overheat it.

18k white gold does not bend, it breaks, most of the time.

Wendy, I use this 18k white gold with an Italian mix very often
from ingots, sheets and wires. It sure is a hard metal, but it
does bend and never breaks.

if it was requested by a customer…just say NO!

One policy I have, If you can do it, in a way or another, never
say NO to a customer. “The customer is a king”

most white gold alloy is made white with nickel or palladium.

Geo, I use both alloys. Palladium, as you said is soft. but I
never tried to cast it. As for the nickel, I use an Italian mix
wich is made of nickel and other metals. This is the one giving
me trouble with casting but not when I work with it from sheets
or wires.

So guys, My next trial is a flask at around 1100 Deg. F. and
Lower torch temperature. i’ll keep you posted.

by the way, i liked your marlin rendering!

Geo, If you need any design in any style, I could send it as an
attachement in an E-mail in most known formats.

Thank you all.

FADY SAWAYA.
@Artemis

#7

I’d really like to find a casting company that is casting
palladium white gold alloys at a reasonable price…

Candia Enterprizes (Candia, NH) casts in palladium white gold,
but I don’t know what their prices are. You can call them at
603-483-2545 and I’m sure they will give you their rates over
the phone. Ask for Brent or Kathy.

Sharon Ziemek


#8

Fady, and everyone else. i have been casting white gold for
years without these problems. i found an alloy that seems to be
near perfect. i use it for 14 and 18kt it does not come out
brittle ever! and i even have taken the same button and used it
to make sheet stock as well as wire stock. i have even melted it
three or four times for different sizes or because of poor ingot
pours. prongs can even be open and closed a couple of times
without breaking. i even use it for pave’. sounds too good to be
true i know, but everyone i give a sample to says that it is all
i say it is. i get this alloy from Heraeus PMR Inc. at 11135
Walden Ave., Alden, NY 14004 (716) 685-2200. the alloy is #40
white.hope this helps you all as much as it did me. oh yes.
usually cast at about 1100 to 1150 depending on the weight of the
piece. melt the alloy and pure gold together in the
crucible,stirring constantly untill all alloy is melted and
mixed. i also Always! use Rey vacu-liners regardless if i am
casting vacuum or centrifical. this really helps releive gas
pressure.hope this helps :slight_smile:

Frank


#9
It is expensive, but try alloying the white gold with platinum. 
Palladium is harder than hell, and besides it has an
inconsistant grain structure.  I use palladium/gold/silver alloy
all the time in dentistry and it is a *HARD*.

Hate to just write to be contrary, but my experience has been
just the opposite.

Years ago I was trying out for a job when the owner handed me a
ring with a plate installed that needed to be brightcut. A
little while later I was done and found that it was the easiest
metal that I had ever engraved outside of platinum. A few months
later, when I was working somewhere else, I asked him what alloy
that was. He told me 40% gold, 40% palladiun and 20% silver. I
have since used similar alloys in 14K with similar results.
Later this week I will make a 14K white Medic Alert pendant that
is allergic to nickel.

Bruce D. Holmgrain
e-mail: @Bruce_Holmgrain
http:\www.knight-hub.com\manmtndense\bhh3.htm
snail mail: pob 7972, McLean, VA 22106-7972
phone:: 703-593-4652


#10

18k w alloyed with nickel has almost all nickel in the alloy

Whoever invented this stuff never had to size an 18kw ring. It
is a really bad alloy and I cringe when anything with that
stamp comes across my bench. For those of you who are unfamilliar
with this mutation of precious metal, 18k white gold does not
bend, it breaks, most of the time. It’s the copper in 14k white
that makes it somewhat easy to work with and it’s missing in the
18k. Nickel does not form a consistent molecular bond with gold
causing all sorts of problems ( I use palladium white gold from
Hoover & Strong). For the person who was asking about casting in
it… if it was requested by a customer…just say NO! Let’s
rid the world of this cruel joke to goldsmiths one and for
all!

I’ll admit that the stuff is hard, that’s one reason I like it.
And, in my opinion, the color is superior to 14k white. It’s a
greyer white, doesn’t have the beige tone of 14k. I wish I could
get my customers to spring for plat.

The palladium alloy is very nice, especially for setting.
However, I’ve been told that it casts one time only. A couple
people I know have had poorer results using sprues & buttons in
their castings with the palladium alloy than the nickel.

I do a few 18kw pieces on a regular basis. You can see one at

If one of mine comes your way, you know where I’m at. :wink:

Dick Caverly


#11

Skip The palladium gold alloys from Hoover & Strong can be
described as buttery. I just finished some pearl rings for a
show- 2 of them have 18k palladium white bezels. They were very
easy to push over.

Richard D Hamilton, Jr.
@rick_hamilton

Shop rule: sailing is mandatory.


#12

Hi Bruce,

The alloys I use come from J.M. Ney Gold co. They are:
Option-79% paladium, 2% gold, 10% copper, and 9% galium it has a
Vickers Hardness of 425!

Sequel- 77.6% paladium, 3.8% gold, 5.6% silver, 6% indium, 4 %
galium, and 3% zinc. Its Vickers Hardness is 240.

By comparison the hardness of dental 18kt. yellow gold is a
Vickers Hardness of 145, and 14kt. yellow jewelry gold is V.H.
of 100-110.

These are figures I just got from the metalurgist at J.M. Ney.
Pure paladium has a hardness harder than platinum.

This is my experience with paladium.

Skip

                                  Skip Meister
                                NRA Endowment and
                                   Instructor
                                @Skip_Meister
                                05/22/9708:46:41

#13

Thanks Sharon- I has a great conversation with Brent and will
definitely use him for some projects. Turns out he knows my last
sales rep, does casting for a few cape jewelers, and has the
right attitude.

Rick
Richard D. Hamilton

Fabricated 14k, 18k, and platinum Jewelry
wax carving, modelmaking, jewelry photography

http://www.rick-hamilton.com
@rick_hamilton


#14

Pure paladium has a hardness harder than platinum.

Hi Skip,

At 20 centigrade (room temperature) platinum has a Vickers
hardness of 55, palladium of 50, according to Degussa’s
Edelmetalltaschenbuch, 2nd ed. 1995. They give HV for an alloy of
4.5% gold, 7.2% silver, 77.3% palladium, 4% tin, 6% gallium and
ruthenium and germanium with 255, for one with less than 2%
gold, 79.7% palladium, less than 2% platinum, 5% copper, 6.5%
tin, 6% gallium and ruthenium with 260. The additional hardness
origins from the addition of gallium, indium, tin, cobalt,
silver, copper, gallium giving the highest increase, copper the
smallest. Markus


#15

Hi Markus,

The gallium and the cobalt must be the culprits then, because I
understand that indium is not very hard. I have used some
Degussa gold alloys in the past and they are super aber sehr
teuer.

Thanks,

Skip

                                  Skip Meister
                                NRA Endowment and
                                   Instructor
                                @Skip_Meister
                                05/25/9700:07:28

#16

The gallium and the cobalt must be the culprits then, because I
understand that indium is not very hard.

Hi Skip,

The original hardness of a pure metal isn’t always a clue what
effect it has to an alloy, take silver, gold and copper, which
are each very soft in the pure state, copper being hardest with
45 HV, but can get as hard as 140 in an alloy of 750 gold, 36
silver and 214 copper (annealed). The indium does add hardness
to the alloy, 10.7% indium by weight increase hardness by about
75 HV. Markus