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Applying Accent Gold for Silver to Sterling
Put pieces to be gilded on a kiln shelf – not touching – and place in kiln. Heat to anything over 1000˚F but don’t exceed 1400˚F. The piece(s) will turn a dull gray in 10 minutes, but probably less. The dull gray is the copper in the piece oxidizing - forming copper oxide. This step will be repeated three times and if you use long tongs the kiln can remain on and you can shuttle the piece or shelf in and out, but be careful.
The dull gray copper oxide on the surface is removed by putting the piece in a pickle solution such as Sparex #2* or other pickle solution available at most jewelry supply houses. While the solution can be cold, it works best when heated to 140˚F. Rinse the piece and dry it then back into the kiln.
* Sparex #2 and similar pickles come in dry form and is safe to ship and to use. It is mixed one ounce Sparex #2 to about 4 oz water to create a working solution that is inflammable, non-explosive solution that is safer than sulphuric acid mixtures and is safe to use when following the directions and cautions that come with the product.. Contains sodium bisulfate.
What is happening is the copper content in sterling that rests on the surface as a part of the mix of silver and copper is being depleted from the surface of the sterling silver piece. By heating it you are transforming the pure copper content into copper oxide. The oxide can then be dissolved into the pickle solution. Less and less copper is left on the surface with each cycle between Step 1 and Step 2 until there is not copper left on the SURFACE of the piece and there ceases to be any formation of gray on the surface of the part. There is still copper INSIDE the piece so it remains stronger than fine silver.
Prepare AGS according to its directions
Apply AGS according to its directions to the desired areas and air dry thoroughly with nothing hotter than warm air.
Torch fire piece in a darkened room to a medium orange color for 7 minutes or kiln fire at 1650˚F for 7 minutes.
Allow piece to air cool then burnish the entire piece.
Last updated on Tue, October 20, 2009 by Metal Clay Guru