Reverend Rob
Posted November 1, 2013 - 9:16am
Solid Gold alloy must be stamped, as per US law, 1906. A Gold test, scratched from the surface of a Gold Filled object, will be positive, unless you scratch deep enough to incude a quantity of the base metal underneath.
Gold filled has been historically a nebulous term, as the thickness of the gold varies widely. Guarantees on the inside of pocket watch casebacks would allude to a number of years for which the watch could be worn without noticeable brassing. There was no way to enforce or track this, and many factors are obviously at play here, so it was banned, but I'm not certain what year that was. I have encountered Gold Fill so thick it is well worn to the point of erasing the engraving, yet no brassing has ocurred.