QuestionI have a fair number of nuggets and flakes that I panned up here in Alaska, and I was wondering if I wanted to go about making something for my girlfriend like a pendant or something how i would go about doing that. I know I would have to refine it and smith the metal to a lower karat to give the alloy a practical hardness.
1. What type of metal would be best to smelt with the gold? 2. Are there any special tools I would need? I have access to a foundry and an acetylene torch, as well as basic chemistry equipment (chemicals, a crucible and the like).
Any insight you could provide would be helpful.
Thank you,
Evan
AnswerHello Evan,
if you have flakes and nuggets, all you need is the crucible,tongs, and a torch, some borax, fine silver, and copper if you wish to alloy it to a lower karat as 24 is quite soft and it iwouold be more prudent to make a pendant out of 18-22kt if you want to retain the colour of the gold (instead of a a pallid 14 kt.) and a mould.
You would coat the crucible with borax by heating it and then when red hot add about a tablespoon or more borax depending on the size of the crucible and swirling it to coat it thoroughly.The crucible will look shiny on the inside when done .It makes it easier to pour and removes any impurities that you can see on the swirling ball of molten metal.A graphite rod will help stirring the metals if you are going to decrease the karat as it removes any impurities from the mass quite well.
A mould can be carved into cuttlefish bobne- for complete directions I would recommend your reading Tim McCreight's book, the Complete Metalsmith, as he explains in detail how to connect the two halves of the cuttlebone mould and to make the pouring spout ( as wide as the carving and with a groove into the top of the design) and to make some strokes with a pencil or carving tool to direct any gasses away from the casting- you can also use a half of the cuttlebone against a firebrick that you have sanded smooth- I use masking tape to hold it closely, and ensure that there are no gaps between brick and bone. After the gold and siolver have melted and mixed you simply pour into the bone mould and wait about ten minutes to remove the finished piece that will then be polished or otherwise finished as desired- a 3M radial bristle disk (go for the light green or blue one at a 3/8" size for a smallish piece they clean and polish it up or a pink disc will matte the finish.. you can order them on line from any number of suppliers) on a Dremel tool works wonderfully on the cheap to clean and polish without a big investment in equipment.
A rock tumbler can be used to finish it too but you need steel shot and a burnishing compound- for one piece one time no point in investing the 100 dollars just for those pieces of equipment..You tube, Make magazine and DIY TV all have videos on line on how to cast in cutlefish.
as for karating the gold the rule is to a gram of gold, .053 g of fine silver gives you 14kt, .073 gives you 18kt and if you want colours you'll need pure copper to make red, peach or pink gold or nickel to make white ( not recommended!)most people react poorly to nickel and it could be a potential allergen and you'll need special solder to connect anything should anything other than a cold connection be needed. If you look at Hoover and Strong's on line catalogue they give you a table for karating gold up or down. It can also be found on the website for ganoksin.com archives in the bench tips section.I haven't enough time to write out all the possibilities but if you'll tell me exactly what colour and karat you want I can jot that out for you if necessary.
all-in-all it's an easy process and as for refining, you shouldn't need much if the flakes and nuggets are pure gold. Do it outdoors if you can just in case there are some nasty elements in the ore that are not evident ( like lead).The entire process after the design is carved into the cuttlefish bone is about a twenty minute process using an oxy/acetylene or mapp gas torch.you need the oxy fuel arrangement ato get to the 1600 degrees to melt the gold in the crucible.If you use a clay or fused crucible that is new you'll have better results than in a crucible that you don't know what has been melted down in it before.I use a different crucible for each metal and each karat as I don't want copper in most of my metals - that is the bane of the jeweler ; firescale and it is caused by cuprous oxides, if you remove the copper from the picture it isn't an issue- unless you need a special colour of gold or a lower karat, or a tough gold ingot or rod for rolling or drawing wire, sheet, tubing or making mokume-gane billets..
So if you get back to me with exactly what karat you are hoping to make and a description of the ore that you think needs refining I can advise you further. Do try and read Tim McCreight's book though it is available at a lot of libraries and gives complete instruction as to how to proceed with no prior experience.
I hope this answers some of your questions, and also if you look at the videos on line they may fill in the gaps I have left in this brief explanation.
Best regards,Ari
