Sciencemadness Discussion Board

Pt (jewelry) Ir/Rh?

dapper - 24-11-2007 at 13:42

I was just wondering what anyone knew about the platinum used as jewelry. I'm looking into purchasing wedding bands and am thinking that I would prefer Pt to Au. I like the fact that it is less reactive and doesn't form amalgams with Hg. I know one sort of alloy is Pt/Ir, but I'm not sure what other sort are common or desirable. Any comments?

solo - 24-11-2007 at 15:09

What's wrong with google .....there is plenty of info out there ....lazy?...... do some of your own research then ask if there is something specific......solo
Ask google....platinum used in jewelry?

The Power of Platinum
Today, most platinum used in jewelry in mined in Russia which controls the amount minded (much like the diamond industry). A large percentage of platinum is ... - 22k - Cached - Similar pages - Note this

Characteristics of Platinum, Rhodium, Iridium, Ruthenium ...
Platinum Group of Metals Used in Jewelry. Platinum Group metals (Pt, Ir, Pd, Ru, Rh, ... Much platinum used in jewelry is composed of 90% platinum and 10% ... - 9k - Cached - Similar pages - Note this

Diamond Buying Guide : Precious Metals Guide : Platinum
The appeal of platinum is in its appearance. Its white luster is unique. It is also the strongest precious metal used in jewelry, and is almost twice as ... - 30k - Cached - Similar pages - Note this

The metal is extensively used in jewelry, wire, and vessels for laboratory ... More than a century ago platinum was used to adulterate gold and was worth ... - 10k - Cached - Similar pages -

Borsheim's : About Precious Metals
One of the most durable of the precious metals used in jewelry, platinum is also prized for its cool white sheen. An ideal setting for any diamond or other ... - 29k - Cached - Similar pages - Note this
When it comes to precious metals and jewelry, you have many choices and knowing ... Called the "King of Metals", platinum is a very heavy (nearly twice the ... - 22k - Cached - Similar pages - Note this

The metal is extensively used in jewelry, wire, and vessels for laboratory use, ... Medication: Platinum metal is used as support for fractured bones. ... - 9k - Cached - Similar pages - Note this

Palladium is widely used in dentistry, often alloyed with gold, and in jewelry, alloyed with platinum. Palladium dispersed on carbon or alumina has ... - 7k - Cached - Similar pages - Note this

22K gold,silver,platinum jewelry gemstone,coins,gems
Common metals used for Jewelry include gold, platinum or silver. Most gold alloys used in Jewelry range from 10K to 22K gold, while platinum alloys range ... - 20k - Cached - Similar pages - Note this

An Overview Of Common Alloys Used In Jewelry
Platinum is used in industry and medicine as well as for fine jewelry applications. In all cases we feel platinum is a wonderful choice for a lifetime of ... - 37k - Cached - Similar pages - Note this

Result Page: over ten pages of hits on platinum used in jewelry

Panache - 25-2-2008 at 03:24

The platinum used in jewelry is generally 96-98% platinum and 2-4% gold or 96-98% platinum and 2-4% copper. These alloy's have better workability than 100% platinum so jeweler's and especially gem-setters (which is a separate trade from jewelers interestingly) prefer this alloy. You can ask for 100% Pt and if held side by side with the same finish there is a noticeable difference, the alloyed always seems a little brighter and the pure a little duller.

More interesting is if your jeweler is any good he will plate your newly crafted piece of platinum jewelry with Rhuthenium. This layer has the same luster and colour of platinum but is harder and as such dulls from micro abrasions much less quickly.

Why not make the jewelry out of Ruthenium i once asked. It's very very very expensive, that's why.

[Edited on 25-2-2008 by Panache]

[Edited on 26-2-2008 by Panache]

[Edited on 26-2-2008 by Panache]

garage chemist - 25-2-2008 at 04:14

No, it's not. Ruthenium is about half as expensive as gold.
What you mean is Rhodium, which is used as a plating on jewelery and does indeed cost about three times as much as platinum.

JohnWW - 25-2-2008 at 05:32

Ru and Os are more reactive than the other platinum group metals, and so would tarnish much more easily. When heated in air, they go straight to the volatile, poisonous tetroxides RuO4 and OsO4, which have a penetrating odor. BTW Os, with a S.G. of about 22, is the heaviest of all known metals, a fact which is correlatable with its also being the element which most easily forms octovalent ompounds (having a maximum possible number of outer electrons available for either the conduction band or as valence electrons).

Fleaker - 25-2-2008 at 10:13

Well that density depends who you ask, who did the calculations etc. SL says Ir is the densest.

It's Rh that's used to plate as garage chemist mentioned. Not Ru; that is mainly used as a hardening agent. It would make pretty, durable jewelery except for the fact that it is nigh impossible to cast!
As for rhodium, it's over four times the cost as platinum.

Saying they have a penetrating odour does not do them justice. I take it that you have never smelled either (good for you!!) I unfortunately have had experiences with both, and I like neither of them very much at all.

Ephoton - 25-2-2008 at 14:47

Rh looks nothing like Pt one shines like a mirror and the other is more dull like a sinker.
If I had a Pt ring and some one plated it with Rh I would be very upset. this for people
who want to buy gold and make it look expensive with a white metal plate.
truly though its just not the same the Pt looks so much more rustic and antique.

Panache - 26-2-2008 at 01:43

i always thought my jeweler was a smack head, now i know its true, HE KNOWS NOTHING!!!!!!!. More likely i have forgotten.
I will not edit my post to replace ruthenium with rhodium though as this will make everyone posting after me appear like cuckoo's.

Waffles - 3-3-2008 at 15:43

Pt/Ir is not commonly used in jewelry- Ir is very hard and difficult to work with, and melts at a much much higher temperature than platinum.

When/if I do the engagement and wedding thing, I know exactly what ring I want to be dealing with- fucking mokume gane, thats what! Platinum, palladium, silver, gold, copper...they all look incredible layered together, in pretty much any combination. If you haven't seen the stuff, google it, now!

Saerynide - 7-4-2008 at 14:55

Don't get Rh. Rh is used too often in cheap costume jewelry (like base metal plated in Rh or Cr) to make it look all bling and sparkly. The luster so high with Rh that it just screams "I'm tryinging to look rich, but I'm really not".

Get Pt. It's my favourite jewelry metal after silver (I like silver more cause of the intricate work that can be done with it - Pt is too hard for that). I have a Pt necklace that belonged to my great grandmother and it's been on my neck since I was freshman in highschool. Pt is duller than white gold, and is about as shiny as silver (though silver is more white/yellow in color and Pt is colorless). Though that is not to say that Pt looks dull - it does shine when it catches light the right way. It just doesnt sparkle with a blinding tacky glare like Cr or Rh.

There is something about the colorless-ness of Pt and it's subtle shine... Really makes you appreciate it's strength, like it really is the noble metal that will last forever no matter what.

triphenylphosphineoxide - 5-12-2008 at 09:51

Sorry to resurrect such an old thread, but the company that just made me redundant after leaving the jewellery supply business was the largest supplier in Australia(Gold) and for most (Platinum Group) alloys S.E.Asia (no I'm not giving their exact name)
@Dapper: Pt/ Ir usually 90%/10% is predominately a medical product, as are high purity 99.0%+ Pt and 95%Pt/5%Rh.
Pt Jewellery is usually 95% Pt 5%Cu.
White Gold used to mean Pt, but now refers to a range of alloys. If the gold purity (carat) is low <14 the adulterants are usually Ni,Ag, or a mixture; 14<ct<22 usually means no Ni but Some Ag and the higher the gold the more Pd.
This company did briefly release a 22 ct line which was 91.6% (22 ct) Au: remainder Pd line as White gold.
@ Panache: Your Jeweller did lie about one thing; Pure precious metals are not sold as 100%: they are sold as 99.2+, 99.5+, 99.9+(fine) or Ultra high Purity 4*9, 5*9 Metals Basis. But he may not have been a smack head. Just before the jewellery division folded a Black Gold Line was tested in Melbourne. This line used a 14 ct(58.3%+)Au, 23(+or-1)%Pd remainder =Base metal. This was then coated twice, First with Ru then with Au. The jewellery blank was them formed and sections of the surface machined out. The Blanks were then heated in an oxidising atmosphere, to produce gold jewellery with black highlights or vice versa. Just before being laid off I met the manager of the Jewellery wholesale business, a man who continually confused Rh and Ru. It's is more than likely that your jeweller had a F***wit for a supplier.
@ Iamthewaffler: I fully agree Just be sure the Ag and Cu are not too high in the composition, which can look an icky green, although Pd will easily swamp them.
@Saerynide: I think I'm in love.