Why Rhodium?

Interesting discussion so far.

Here's an experiment I tried several weeks ago, although it's not specifically about Rhodium it is related to the conversation.

I've been using an Acrolink 6N-P4039 PC terminated with Oyaide P-004 & C-004 on my amp. I like this cable a lot in this position. This is a high purity copper unshielded cable. The Oyaides are beryllium copper plated with platinum then palladium.

I replaced the Oyaide C-004 IEC with a Fim model 302 IEC. The Fim is gold plated high purity copper. This one termination is the only change I made to my entire system.

The deep bass and punch diminished significantly. I was surprised how much difference I was hearing because, frankly, I expected any difference, if audible, to be subtle.
When I replaced the Oyaide the bass returned.
Note: Male Oyaide was plugged into Oyaide R-1 outlet.

I did this experiment because the amp IEC is a gold plated Furutech and I thought like metals might be the way to go.

Footnotes:
1. I like the Fim terminations in other applications but not this one.
2. I also like Fim outlets.
3. I'm not even pretending I understand any of this but it's fun and interesting.

Mooglie,
I agree that nickel probably has no place in audiophile cabling. On an interesting note I found that the elements name is derived from the German word nickel, which means "Old Nick", a name for the devil. I think in this application he's messing with "good" sound. 8^)
On a related note, I'm not sure brass is all that "good" either and I'm trying to "exorcise" it from my PCs as much as possible. It's amazing how much brass is in most PCs even the megabuck varieties.