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"So, Rhodium costs almost twice as much as Platinum - of course I am interested." Gotta love that.

2006

So, Rhodium costs almost twice as much as Platinum - of course I am interested." Gotta love that

Of course, that's why we're all interested in precious metals, they're precious ;)

Anyways, my question is along the same lines as these guys': Is it possible for necklaces/rings/bracelets to be made from pure iridium? Or partially iridium? From what I understand (correct me if I'm wrong), iridium is shinier and more expensive than silver, no? Might be a nice medium for people who can't afford real PL platinum or any of the other platinum metals.... but I'm just an enthusiast...

Russell Rounds

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2006

Hi Russell,
Pure Iridium is not used in making jewelry for a few reasons. The pure metal has very few applications because it's very hard to work work with. In it's pure state it is very hard and brittle. It is also rare, which makes it hard to get. Iridium is often used as an alloy in platinum jewelry. The only "affordable" alternative I know of (without sacrificing quality and prestige), is to purchase platinum jewelry with a 25% alloy range. The alloy make-up could contain iridium, copper, osmium, rhodium, to name a few. You know the old saying Russell, "you get what you pay for".
Regards,

Mark Baker

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2006

Compositions of platinum jewelry alloys are somewhat limited by law. Pt-5%Ir and Pt-10%Ir alloys can be used. Iridium could be sold as such, but has a much higher melting point, so more difficult to cast.
Platinum group metal prices, from Johnson Matthey (London), May 12, 2006, plus melting points:

RHODIUM US$5300/troy oz, 1963 C (melting point)
PLATINUM 1340 1769 C
PALLADIUM 405 1575 C
IRIDIUM 385 2447 C
RUTHENIUM 180 2334 C.

For information on platinum jewelry (jewellery in the UK) alloys, see http://www.platinum.matthey.com/applications/jewellery.html and the pdf link.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.