Hi Guys & Gals,
I've been hunting for close to 10 years on the coast and have seen ALL types/grades of oxidation on various metals (or so I thought) but have to admit, I am gobsmacked!
....took out a big, thick "ring" and on visual ID was immediately excommunicated to the costume jewelry section (although Xterra 705 with 18.75khz coil gave TID of a solid 28) also as it looked like a large old piece of galvanized pipe inclusive of small rust nodules all over the surface. Looked seriously k...k! Was deciding if it even should do life in the costume section...or coup de grace it in the bin..
However....the missus was adamant that it be cleaned, so it went straight in the vinegar bath..
1 Hour later out pops this BIG gold men's wedding band!! Perfect! and no, it is NOT plated...
Did some research and turns out that under certain very specific conditions, gold can and will tarnish, the rust nodules not originating from the gold itself but from water high in chlorides and where iron (from pipe-work) is dissolved and through a electrolysis reaction attracts the rust onto it's surface...something I have never thought possible!
Point being...in future I am making VERY sure of everything before binning it...no matter how crap it looks...take note amigos