koftgari preservation question

mariusgmioc · 17th September 2017, 09:56 PM

Quote:

Originally Posted by silberschatzimsee

Hi Marius,

thank you very much for your information. After sleeping over it i thought takeing it to an expert would be a better option. First of all it was quite expensive and it would be a real shame if i try to "optimise" it and ruin it forever by doing so and fail miserably at it.

Its very hard not to give in the urge to present it already now, so will present it to the forums for discussion when everything is finished.

Thanks again

Good luck!

But please make sure you check how expert is your expert and ask him if he has experience with this kind of work.

Philip · 17th September 2017, 11:54 PM

Marius you have posted some very sound advice about preservation. The trouble with koftgari is that corrosion that starts in the exposed iron around the gold decorative motifs can eventually eat underneath the precious metal (which after all is a thin foil on top of a roughened surface, a mechanical bond without any chemical adhesion or sealing whatsoever). This corrosion going underneath is what causes exfoliation.

Using waxes and other things is of little use in areas where the corrosion is still working, and not removed. The rust will keep going, over long enough time, under the wax. I make it a point to remove as much of the visible rust BETWEEN the decorative elements, using fine dentistry tools and micro diamond rifflers, without disturbing the overlay or leaving patches of bright over-cleaned metal. It can be a slow process, not very exciting work, but at least you know that your item will survived that much longer with its decoration intact, after you do the final cleanup and apply your wax coat.

silberschatzimsee · 18th September 2017, 01:04 AM

Hi Philip,

I have no rust or other issues. I just want to have its current status preserved

Using tools is not good on my thing because the koftgari is on top of blue steel and polishing it would take away that layer of colour.

17th September 2017, 11:54 PM	#2
Philip Member Join Date: Dec 2004 Location: California Posts: 1,036	Marius you have posted some very sound advice about preservation. The trouble with koftgari is that corrosion that starts in the exposed iron around the gold decorative motifs can eventually eat underneath the precious metal (which after all is a thin foil on top of a roughened surface, a mechanical bond without any chemical adhesion or sealing whatsoever). This corrosion going underneath is what causes exfoliation. Using waxes and other things is of little use in areas where the corrosion is still working, and not removed. The rust will keep going, over long enough time, under the wax. I make it a point to remove as much of the visible rust BETWEEN the decorative elements, using fine dentistry tools and micro diamond rifflers, without disturbing the overlay or leaving patches of bright over-cleaned metal. It can be a slow process, not very exciting work, but at least you know that your item will survived that much longer with its decoration intact, after you do the final cleanup and apply your wax coat.

18th September 2017, 01:04 AM	#3
silberschatzimsee Member Join Date: Aug 2015 Posts: 90	Hi Philip, I have no rust or other issues. I just want to have its current status preserved Using tools is not good on my thing because the koftgari is on top of blue steel and polishing it would take away that layer of colour.