Where and how do you position a kilt pin?

[Paul Henry]

gold doesn't oxidise....... that's the beauty of it....

[Nanook]

gold doesn't oxidise....... that's the beauty of it....

While the element Gold does not oxidize and is generally unreactive:

• Pure gold is NEVER used for jewelry. Its not suitable. Its too soft.
• Most gold kilt pins are made from alloys and material mixes that do tarnish.
• Contemporary gold pins are typically 14kt or lesser or 18-kt plated silver.
• Even 14-kt Gold does tarnish. The air we live in is filled with environmental pollutants that will react quickly with its silver and copper.
• Common antique gold kilt pins were in their day cheap "costume pieces". I don't think I've seen a really good gold kilt pin and most of the "better" pieces where made of sterling silver. The gold pins I've seen are often made of either 12-kt gold plated--- and most old pieces have less than fully intact plating--- metal or 8-kt (Gold 333) gold.

Remove silver stains?
This is a difficult one as one has not just the wool material but also the dyes to worry about. If you think about it your stain is not unlike colour photographic film. The typical solutions to removing silver from clothing are either to use a RA-4 blix (Bleach-Fix) with maybe some added disodium EDTA or Farmer's Reducer (also a photographic bleach)--- note that modern BLIXs don't use potassium ferricyanide (as does Farmer's Reducer) but Ferric Ammonium EDTA (which, I think, is probably the preferred bleach here).
WARNING WARNING WARNING. As with ALL stain removal one must ***first*** fully test the results as the potential damage caused by an attempt to remove a stain can be many times more serious that the original stain.. Again.. I repeat.. using ANY BLEACH (and BLIX as well as Farmer's Reducer ARE bleaches) can create significant damage. WARNING WARNING WARNING.