Can someone out there in Orchidland explain to me the fascination
with 18K white gold? I love the white metals and I understand the
wonderful karat differences between other colors of gold but why
would a customer buy a costlier 18K white gold object that looks the
same as a 14K white gold object? What are the selling points?
Orchid Rules! Karla in S. California
I do find a difference in the color from the 14kw to 18kw, even more
so with pladium white( gray in tone).The standard 18k white I have
used is whiter with less yellow tones .I generally use a low nickel
14kw from DH Fell& co,the non pladium white I have tried has better
color but it is very trickey to cast.For me it tends to come up
with a fine poristy problem that I do not have with the others
alloys I use. Any feed back on that problem would be appreciated.
I prefer to go with the natural color of the alloy than having to do
a rhodium finish.
Hi Karla, You ask why would someone want 18kt white gold? Well one of
the major reasons 18kt white that is alloyed white palladium is used
is that it is a wonderful material to set stones in. It behaves much
like platinum at a fraction of the cost. Another reason one might
choose 18kt white is that it is sort of greyish brown in color rather
than the purew white of platinum. For certain married metal pieces it
gives an interesting color contrast. I have also used it for men’s
jewelry where I find the color is suitable. If you are looking for an
inexpensive durable white precious metal, then you are right. 14kt
white gold is great unless of course your client is allergic to the
nickel in most white. However in the end nothing beats platinum as a
white jewelers metal. etienne@etienne.com
Karla, As to the selling points of 18kt white gold; just the fact
that the gold content is 75% as opposed to 58.5% substantiates the
higher price over a similar item in 14kt. Aesthetically the 18kt
palladium white gold alloys are fantastic metals to work with, there
is no comparison, between the two karats aside from the color. And,
in my opinion the superiority of the 18kt metal’s performance
outweighs the slight difference in color. I have not yet had any of
the galleries which represent my work comment that their clientele
didn’t find 18kt white gold to be white enough. As with most
precious commodities, purer is better! 
Michael David Sturlin, jewelry artist @Michael_David_Sturli
https://www.ganoksin.com/orchid/sturlin.htm
Karla, I think that some people just like to know that the alloy
contains 75% pure gold versus the lower gold content of 14K. To my
eye, 14K white looks whiter than 18K white. Joel
Joel Schwalb
@Joel_Schwalb
www.schwalbstudio.com
color but it is very trickey to cast.For me it tends to come up with a fine poristy problem that I do not have with the others alloys I use. Any feed back on that problem would be appreciated.
Hi Michael: Porosity can be caused by a number of things. Improper
sprueing and casting with the mold at the wrong temperature are the
most common culprits. I try to “think like the molten metal” when
sprueing. It doesn’t like bottle-necks and doesn’t like to go around
sharp corners. Large masses of metal shrink as they cool, and need
some more molten metal to draw from (dead-sprue) or they’ll pull
themselves apart at the surface. When possible, have metal flow from
thick to thin. I prefer vacuum assist, with a mold temperature of
about 850-900 F. depending on the thickness of the article (thinner
needs slightly hotter). For centrifugal, and especially with silver,
I’ll cast as low as 700 F. But in the case of palladium alloys, I
would suspect another factor. The crystobolite based investments
(standard investments) can negatively affect palladium. Invest with
a plaster designed for platinum casting. The traditional
non-crystobolite investment used in platinum casting uses a catalyst,
which is mixed with the water used in investing. This type of
investment takes 8-12 hours to set up, and should be used with paper
towels instead of the rubber base (this is a real pain to set up) as
it needs to have the water “wicked-off”. PM West has a new quick
setting non-crystobolite investment they sell through RioGrande that
is a lot easier to use. It behaves like standard investment. Also,
you shouldn’t melt your palladium alloy in an “electro-melt” or with
acetylene fuel. It would be preferred to melt in a ceramic crucible
(for vacuum assist) or directly in the crucible of your centrifugal
casting machine using propane or natural gas. This avoids
contaminating the palladium with too much carbon. I don’t know what
the situation is pertinent to induction casting. (Daniel Grandi
would know about it, I’d wager).
David L. Huffman
If we’re talking about nickel white golds, then 18k NICKEL white is
much harder than 14k NICKEL white. It doesn’t seem like it would be
true, but it is.
Andy Cooperman
Hi David and Thank you for your response,
I also cast at 900 F and use vacuum assist castings,( by the way the
new and approved wax web from rio is working great) .I think my
problem is the certain alloy, This is a low nickel and no palladium
alloy in 18k white,the color is nice, easy to set not as hard as the
nickel white.
here is a link to dhf on this gold alloy
http://dhfco.com/pages/gold_karat.html#plus6b
Over heating seems to be the biggest possibility, i have called DHF
and it does seem to be a more problematic alloy , i noticed they are
calling the 18k white plus a new alloy I may not have tried this
particular one but I do use the other plus alloys with great
results.Has any one else been using these specific alloys including
the 18k white plus.I really want to do more 18k white casting but
this fine porosity problem has kept me from that direction.
Michael Devlin
