Hi All, I’m hoping to get two cents from anyone with more experience
than I have in working with platinum and white gold. If I have
identical rings cast in the two materials which is more likely to
bend/get a flat spot when put under pressure or knocked pretty hard
against something while being worn? I know platinum is much more
dense but have had no real experience in comparing their other
properties.
Thanks for any help!
Cheers,
Julia Turner
San Francisco
Hi All, I'm hoping to get two cents from anyone with more experience than I have in working with platinum and white gold. If I have identical rings cast in the two materials which is more likely to bend/get a flat spot when put under pressure or knocked pretty hard against something while being worn? I know platinum is much more dense but have had no real experience in comparing their other properties.
It depends some on which alloys. Some white golds, particularly the
palladium white golds, can be quite soft, while some platinum alloys
are designed for heat treatment to harden them (like the Hoover and
Strong Platinum-SK alloys) The latter can be made springy and stiff
and quite resistant to any deformation. But with the commonly used
10% iridium platinum, castings tend to be relatively soft. some of
the other common platinum alloys are even softer. Meanwhile, normal
nickle based white golds, and especially the 'superwhite" 18K white
golds are hard and stiff enough that I know at least one diamond
setter who refuses to do certain types of setting work in those
alloys. Between these two types, the white gold will be MUCH more
resistant to bending and denting and scratching. However, even
though the platinum ring seems softer and easier to deform, it will
resist wearing away a lot longer. The white gold may be stiff and
hard, but over time with wear, prongs and shanks, etc, will get worn
thinner much faster than with the platinum, which even with dents and
bending, might still last lifetimes. And if the platinum is work
hardened a bit, such as in casting the shank thicker and smaller
than desired, and you then forge the shank up in size, thus working
the metal, the bending and distortion can also be greatly reduced to
the point where it’s not so much of a problem at all. It also
depends a lot on how delicate your design is. If you make a size 8
ring in cast platinum, with a shank that’s 1.2 mm wide and .7 mm
thick, this is gonna bend way out of shape before you’ve worn it two
days. Make it twice that in both dimentions, and it can be
reasonably sturdy. Heavier still, and it won’t be bending much from
routine normal wear. And if you can fabricate significant portions
of the ring from drawn wire and rolled sheet metal, and the like,
you find the distortion, bending, and denting problems are GREATLY
reduced. Rolled and drawn metal is denser, with a finer crystal
structure, and holds up to wear and tear a lot better than most
platinum castings.
Peter Rowe
It will depend on how the platinum ring was made and what alloy of
platinum it is made from ( there are at least half a dozen in common
use in the US). Some platinum alloys approach medium carbon steel
for hardness and are harder than any other common jewelry metal but
the majority of cast platinum rings are very soft and scratch. bend
and dent easily. On the white gold side it also depends on the
alloy. Nickel white golds are quite hard and will not easily dent or
bend. The down side is that they are not very white and are in need
of Rhodium plating to look “white” so the plating wears off fairly
fast and the ring ceases to look very good where it is worn. Also a
significant portion of the population has a severe skin reaction
with nickel and will not be able to wear it. Most palladium white
golds are grey (just a little bit darker than platinum) not white
but they are much softer than nickel white. So It all depends on
what alloys you are referring to.
Jim
Hi Julia, Which platinum we are using for comparison matters.
All nickel based white gold is very hard, very resistant to bending
or denting. Cracking is the risk with nickel whites for excessive
hardness. Annealing white gold for fabrication is a real trick.
Traditional platinum like 90Pt/10Iridium, and 95Pt/5 Ruthenium is
fairly soft by comparison and has more chance of bending or denting.
If one cast the same ring in 14kw and platinum they would se that
platinum is nearly twice as heavy as 14KT gold. That makes one heck
of an impression on the consumer that tries both on.
If your customer wants platinum, and there is a strength issue- Get
one of the “heat treatable” platinum’s from Imperial smelting
(Canada) Hoover & Strong, or even Englehard, perhaps via a
distributor.
Good Question!
Daniel Ballard
Julia - If I remember correctly from your previous posting, you are
making wedding rings for friends. If they’re looking for a white
metal, I would always suggest platinum over gold. Definitely a
personal preference, but it’s truly white and it’s durable. Also
more expensive, but these are important rings. Platinum, however,
especially with active people, tends to lose its polish and go
somewhat matte, while gold maintains the polish longer. I love the
look; I also think that matte platinum looks fantastic when paired
with gold, especially higher karat.
As an example: My wedding ring is a 5x1.5mm 18ky gold band, with a
3x1.5mm platinum half-round band sitting on top (all fabricated).
My husband’s is the same (although mine has a little bezel set
diamond on top). I’m tough on rings, but my husband is a lapidary
and rockhound – i.e., loves abrasives, heavy rocks and hammers –
and doesn’t take his rings off when he should. In the last two
years he has actually managed to remove a small chunk of the
platinum (which I’ll kindly consider a gift for the gods), in
addition to inflicting some minor scratches. The platinum
(originally a high polish) has developed a lovely matte and
decidedly worn finish, but is not otherwise dented, while the gold
still looks fairly polished but is dented on the edges, and also has
a few minor scratches. It’s 18k, so 14k would be somewhat more
durable. Mine has some slight scratches on both pt and gold, and a
couple of dents on the gold. If I were to remake them, I would use
the same materials because I love how beautiful they are.
I hope this helps,
~kara