Golden conductors in a vintage Japanese cable?

I’ve got these vintage Isoda HA-20 “hybrid” speaker cables. Info is very scarce and probably mostly in Japanese
They sound pretty nice, so I decided to cut away the resistive banana connectors. Now, to my surprise, there appears to be one part copper, one part silver and one part something that really does look like GOLD.
Could it be gold, since wouldn’t that make these very valuable? I haven’t even today heard of but one manufacturer (Stealth) using gold in speaker cables.

What else could it be, that is the color of gold? Or just a plating, if so, why?
As it’s labeled a hybrid cable, the trio of Cu, Ag and Au would certainly make sense… It’s meticulous Japanese design, the conductor strands are actually “twirly” in shape. Might affect inductive interaction between the strands?

There was an article that suggested Isoda designs were actually what were a sort of precursor to the quite famous Auditorium 23 cables…

Gabriel Gold interconnects use gold and silver in their top line offerings also…they sound wonderful!!!

Yes. There are some manufacturers of very revered golden interconnects, Teresonic, DualConnect, a few others…
But using it in speaker cable? It WOULD be costly but hey, we might like the results if the geometry is up to the job.

The cost makes me question if it really is gold that’s 1/3 of the conductors in these vintage cables. What could it be? It does look like gold.

Yes…speaker wire would be costly no doubt. Maybe gold plating over silver in the Isoda?

Do you think having gold-plated silver / gold-plated copper alongside both unplated, would make a difference in the cable’s signature?
Could it be some alloy that’s gold-coloured? A zinc alloy…?

Okay here’s a closeup of the strands, in bright light.

By the way is it probable that the twisted construction of the strands alleviates inter-strand inductive problems to a degree?

I have doubts what you are ascribing to a difference in conductor material really is. Looks like thin film insulation of a different type on different strands. Plenty of popular thin polymers have colors that, when applied on a conductor, could be mistaken for the color of a familiar metal itself. Unless the silver on the ends of those ‘gold’ conductors is tinning (could be, not discernable from that photo) there is no reason a ‘gold’ conductor changes to silver. Ditto one of those ‘copper’ strands that changes to silver as well. I’m not going to get into the ‘hybrid’ part of the description because I’ve seen that term used and abused in the past for all kinds of designs where what is being described is really a mixture of insulators and not conductor material.

Ohh, no no. Just a bad picture. The strands are continuous in their colour… And certainly their surface looks like metallic sheen. Dunno if polymers can be thin enough to allow for copper to look like copper.
What is clear is that there are three different conductor materials here. Don’t think they’d have individual insulators underneath the main outer polymer mixture that kinda presses these conductors into a tight bunch.
Also, the strands aren’t supposed to be visible. I cut the original banana connectors away for bare strand connection. Got better sound, obviously.

Even if they were “color-coded” for practical reasons in production, there’s still three different conductors. What could they be? I’d wager copper and either tinned copper or silver and… a mystery material.

In bright light, the supposed “gold” strands take on a greenish-yellow colour. This isn’t exactly how pure gold would reflect, besides it couldn’t be 24K anyway due to softness. I guess the twirled structure of these conductors gives some strength, but still… here’s a diagram of hues of gold alloys:

Could it be a significantly cheaper alloy of gold, apparently approximately half silver? Can’t be sure but the hues match.

An interesting tidbit: The Isoda cables were apparently a precursor or inspiration of sorts for the famous Auditorium 23. The article says that “Isoda-san took long to harmonize his cables”.
Well… they are surprisingly good given that they don’t really have geometry other than individual twirls.

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Any ideas what it could be? Never encountered a conductor of this color. Actually not even in pictures.
Actually… yes, the Silversmith Fidelium is this color!