platinum alloy mixes....please help!

[Metalman]

Hi,
I am in the process of purchasing a platinum ring from melbourne diamond exchange.
I asked for the type of mix they use and was told it was 97%, with the 3% consisting of zinc, cadmium and one other metal they couldn''t remember the name of.
I have searched the internet for info on this mix but have not found anything.
Can anyone advise me as to the suitability of this alloy mix for a ring? (i am setting a G colored stone into it)
What is the hardness. Does it tarnish? Does it need to be coated every 6 months or so??
Thanks
Metalman

 

[niceice]

We've put together a page on Platinum that covers the more common questions and concerns regarding platinum and the common mixes of platinum are indicated towards the bottom of the page. The 97% (970) mixture is not familiar to us, but it might be fairly common in Australia, why don't you give Garry Holloway (Cut Nut) a holler and see if he is familiar with it since he's in Australia...