Information on the pick up is both plentiful and contradictory. Particularly on the Internet.
There is one indisputable fact, if you're selling the right one (there's many different variations), you can get up at $300 for it.
Most are just simple magnet pick ups that had a textured gold foil-like covering placed on them, but a thin metal casing placed on top (but with the gold foil showing through).
The story about the rising popularity of the gold foil begins like many other guitar fads, the right celebrity used one, and as a result it became fashionable to have one. That type pick up had already been put into a modern guitar, like with the guitarist for the Cure, but it didn't have much effect on guitar fashion.
That guitar player was Ry Cooder, who's as respected a guitar player, at least among other guitar players, as a player can get.
The story begins when David Lindley, another respected slide guitar player, gave Cooder a gold foil pick up. He had it mounted in the middle position on a Stratocaster (which has three pick ups), but here's an important point, the third pick up, or what they called the bridge pick up nearest the bridge was a pick up taken from an old lap steel guitar. That's the pick up you probably hear more often on his records than the gold foil.
That version of the stratocaster is now nicknamed the Cooder caster.
In a past interview that I read, and I'm afraid I can't recall the publication, he liked the gold foil because of what guitarists call it's "clean sound,"or undistorted tone. He felt that the sound had a clarity that had a sort of open transparent quality to it.
That's the primary reason he it had put in, and that's the main reason he uses it.
Around the same time, after all nothing happens in a vacuum, the prices of regular Fender guitars and Gibsons were going up drastically due to collectors.
One of the results of this was that the older Japanese guitars made in the 60s started to become popular as collectors items that were both unique and still at the time affordable.
I think these two factors combined to make the gold foil pick up popular. That plus the fact that some of the gold foils were made by the Dearmond company, who were at one time legendary for their pick ups on now vintage Gretsch guitars and on their own branded models.
The fact that a bigger company like Dearmond made some cheaper pick ups for the Japanese models wasn't an unusual practice.
The now famous Buck Owen guitars, which were made cheap at the request of Owens himself, who felt that an expensive custom version wouldn't be affordable by most of his fans, turned out to be very valuable guitars.
The reason?
It turns out that Gibson wanted the contract very badly, if for no other reason to keep the production lines going in its factories, so they became the subcontractor that produced them. So those cheap Buck Owens guitars with the US flag coloring are now expensive collectors items because it's now known that those were made by Gibson.
Yet another cheap guitar I bought cheap and sold cheap...
So a cheap Harmony brand guitar could have well made Dearmond made pick ups on it.
In any case, gold foil pick ups became very popular. In fact some people would buy the old Japanese guitar, take off the pick ups, and toss the rest of it away.
Since the guitars were cheaply made, that may have been the best fate for a few of them, but the Japanese made higher end guitars also that even today are still in good shape and it's hard to estimate how many of those were destroyed in the quest to get at those gold for pick ups.
You would think that after a few years this craze would've died down. After all, not all of those players are going to use that gold pick up like Ry Cooder did.
In fact, the opposite happened. The gold foil pick up became even more popular, as it turned out the things had a distinct sound even at rock 'n roll volume levels.
Guitar players not only kept the original Teiscos, Kay's, Harmony, and other cheapies, but put the pick up in some of the other guitars like Fender telecasters.
If you look at the numerous videos on YouTube of guitarists demonstrating their guitar with the gold foil pick ups, very few of them use those like Ry Cooder does.
Most use them like cranked up Gretsch guitars. Which makes sense, to me most of the gold foils have a sort of bright crunchy Dearmond sound, and that company made pick ups for Gretsch for years.
There is an irony to that because there's plenty of modern Dearmond gold foil pick ups on the market that are much cheaper and I think have more output and sound better.
Now that's what I think. On the discussion boards, it's become a cork sniffing debate with all sorts of reasons why the older ones are better than the new and vice versa.
Like probably more than a few guitar players, I got a hold of an old Japanese guitar myself with the gold foil pick up. I guess I just had to know.
I compared it to a Crown Kawai-Tiesco that I had, a mahogany body telecaster with a 70s era the Demarzio distortion humbucker in the bridge, and an Eric Clapton signature model Stratocaster.
I put the two Fenders away almost immediately, the gold foil to my ears wasn't even close. It did have more output and brightness than the Crown, and at rock 'n roll volume, the gold foil had a beautiful clarity and power.
However, the Crown had a cleaner more crystal-like clean tone, similar to a Fender Jazzmaster, and at high-volume, had more of a late 60s and early 70s Stones sound. Which is why I still have the Crown.
The gold foil, to my ears (and for accuracy I should note that I was using the "slim Jim" version most popular for mounting into telecasters) seemed more suitable for roots rock and rockabilly, and trash guitar like Link Wray. Not bad at all either.
I didn't bother to do much on slide since on the few occasions when I do use one, my approach and technique is nowhere similar to Ry Cooder's. I did do some light single string slide riffs, and I would have to say, I think it does have that glassy transparent sound he liked so much.
I should add, that a Dearmond guitar with the more modern gold foil pick ups can get the same sound if you set the amp correctly.
So on one hand, there have been some that criticize the use of gold for pick ups as simply a fashion simply due to Ry Cooder using one. It certainly has made the pick up a lot more expensive than it should be.
On the other hand, I lean towards the opinion that Cooder may have made it popular to use one again, but the real result is that an old classic pick up has found new life again. Evidenced by the fact that some of the more famous boutique pick up makers are now making their own versions of gold foils.
It may have started off as a fad, but it's now become one of the standard options that guitarists can pick from to shape their sound.
I don't think these gold foils are going to go away anytime soon, but don't buy one for investment purposes. As these get more popular, and given how cheap it was to make them, it won't be long before they come down to the price of most modern pick ups.
