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Question about the use of gold
stoneaddict -
Tuesday, September 22, 2009 - 11:47am
Gold I recently bought some 18 kt gold bezel from Rio Grande to set a nice stone in. My first time working with gold. It was so rigid! Even after I annealed it! And because of that SO hard to push down over the stone. I thought I'd break the stone! Compared to gold, silver is like BUTTAH. Is this normal? I also bought some gold solder to flood in stamped areas for decoration, and it, too, is very rigid and brittle. What's the deal- I thought gold was so nice to work with???  It's normal. Using gold
Dick C -
Tuesday, September 22, 2009 - 12:57pm
It's normal. Using gold bezel wire in the same manner you might use silver will definitely be more difficult. A closer fit to the stone is desirable, and, because it's springier, you may want to burnish or tap the top edge to move the metal onto the stone instead of just pushing the bezel toward the stone. I have a chart of Vickers hardnesses for silver and gold alloys. Here are a few: Fine silver - HV 35 Sterling Silver - HV 75 18 kt. yellow - HV 155 - 125 (two different alloys from Hoover & Strong) 14 kt. yellow - HV 145 - 195 (two different alloys from Hoover & Strong) 22 kt. - HV 60 24 kt. - HV 30 18 kt. white (nickel) is really tough - HV 265 That info was out of a
Dick C -
Wednesday, September 23, 2009 - 10:38am
That info was out of a Hoover & Strong catalog. I looked and see that the full chart is up at their web site. Go to mill products > casting grain specifications.  casting specs chart
stoneaddict -
Wednesday, September 30, 2009 - 12:08pm
Thanks, Dick! That chart at Hoover and Strong is DA BOMB. I'm going to laminate it and tack it prominently in my studio. How did I get along without it before???? Keep in mind that it refers
Dick C -
Wednesday, September 30, 2009 - 12:17pm
Keep in mind that it refers specifically to their alloys. 22 kt, which is over 90%
Dick C -
Thursday, October 1, 2009 - 12:30pm
22 kt, which is over 90% gold alloyed with just copper and silver isn't going to differ to any noticeable degree from supplier to supplier, I wouldn't think. The point I was making was that with most of the lower karat alloys -- which are proprietary and contain larger percentages of multiple alloying metals, things like melt and flow temps, hardness, etc, are specific to their products. If I used someone else's 14 kt casting grain I'd get recommended temperatures from that supplier. That chart, however, can still throw some light on the nature of gold alloys.
 bezel setting
silvermon -
Tuesday, September 22, 2009 - 8:30pm
While silver (fine or sterling) bezels can be easily set tight to the stone with a standard steel burnishing tool, gold bezels are first closed (but not tight yet) with a rolling action supplied by a closing tool, whose exact name escapes me right now, but is a small curved piece of steel with a handle that can roll down about 3/8'' of the bezel diameter per one wrist motion. For really large stones you will want to partially close spaced out lengths of the bezel so you won't create a twist in the bezel; kind of like stitch welding or tack welding. The gold bezel is still finished up with a standard burnishing tool; trying to roll the bezel to it's final tightness against the stone can cause cracking. Practice is required.  tools and gold bezels
Stefani -
Friday, January 15, 2010 - 3:51pm
I would say the name of the tool is a "rocker", which is just about what you do with it. You slowly rock the tool back and forth as you work your way around the bezel, being very careful not to let the metal fold. I usually use one and then a burnisher. I suggest getting used to the lower karat gold unless you prefer the color of higher karat gold. You can always plate it. The lower karat gold will be far more durable and less easily pushed out of shape, nicked or cut. Silver is like butta. It wears like butta too.  The advice given is all
Rich Waugh -
Wednesday, September 23, 2009 - 9:51am
The advice given is all correct - for ease of setting, you'll find 22kt more pleasant to work with. One caution, however; if not burnished down thoroughly, it will not work harden sufficiently to ensure secure retention of the stone. No need to anneal first, just roll down with a bezel pusher then burnish to a smooth, hard edge and it will work fine. For filling engraving or etching to develop color inlays, I recommend fine gold if the area is not subject to heavy wear. If it is likely to be rubbed a lot, then I'd suggest using 22kt. Note that both of these have higher melting points than the lower alloys so you need to check to be sure you're not going to melt your base metal before the gold flows. One way around the melting point problem is to use SilFos (phosphor bronze) for the filler. It doesn't have the nice yellow color of gold, but it does have a good, pleasing contrast with silver. Best of luck, Rich |
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ArtMetal
I found the same thing with
I found the same thing with 14kt gold and thought 18 would be better. Guess not. If you were using the gold solder for decorative purposes, perhaps a more rigid base would help.
marilyn