We have discussed with you permagold in a PM.
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Permagold is an alloy often used in jewellery, looks like gold and is not it was used in at least two different brands Dolnet used it only on the ROYAL JAZZ model and SML used it too.
Perma-gold is Zinc Dichromate it is a trade mark name
In the case of saxophone finishes, not all that glitters is gold. Buyers and sellers often mistake lacquer for gold plate, but Perma-gold looks even more like gold. Perma-what? It’s a dichromate mineral-based coating that typically goes over a metal like zinc, or possibly nickel. This short post...
Perma-Gold is mostly a curiosity, but it is important when buying a vintage SML (Strasser Marigaux Lemaire) saxophone. There may also be perma-gold Selmers, because there are vintage Selmers (Modele 26-era) whose finish is marked PG in the log books. Who knows? Let me know in the comments if you happen to own one!
Permagold looks a lot like gold – so much so that it has been banned in some countries for use in jewelry! So one can hardly fault sellers of permagold-plated SML saxophones for selling their horns as gold-plated...."
To complicate matters, since gold plate is usually applied over silver plate on saxophones, and silver looks a lot like zinc, even partially worn-off permagold still looks superficially like worn gold plate. But if you are in the market for a nice SML, here is how to tell the difference.
1. Every permagold SML so far has shown a distinctive flaky pattern to the wear. I suspect that this is because dichromate is a mineral, so it flakes off in little chips, whereas gold wears off like metals do, rubbing uniformly thinner on touch points until the silver underneath starts to show through gradually. It also burns off like lacquer, but is even more fragile. Check out the neck tenon burn mark on my SML tenor....."