Adventures in Alloying: Recycling and alloying wedding bands from 22k gold into 18k gold

Earlier this year I was commissioned to recycle two 22k yellow gold wedding bands into two court shaped 18k white gold wedding bands. Cool, right? Well, to be honest, it was going to be a challenge. Recycling metal is something I am proficient in, but alloying to a different colour or cartage - well, that was going to be new!

Original 22k gold wedding bands before being recycled

To be fair, alloying the gold was not part of my clients' original brief. They wanted the gold of their family heirlooms to remain 22k gold, but when I learned that the engagement ring was made of 18k white gold, I realised that that was not going to be a happy marriage (of rings, that is). So, I suggested they consider alloying down their rings to match her 18k gold engagement ring.

This suggestion was not for any aesthetic reasons, but a practical one of longevity. As the bride-to-be intended to wear her wedding band next to her existing engagement ring, I recommended that the band ought to be at least a similar caratage of gold, if not colour as well. The reason is because 22k gold is softer than 18k gold, and over an extended period of time (e.g. several years) the harder metal of the engagement ring will wear away a softer band.

(For a more technical explanation, 22k gold has at least 91.67% gold content with the rest being a combination of silver and/or copper; 18k white gold has a minimum 75% gold with the remaining 25% being a combination of silver, copper and palladium - and it is the higher presence of these other alloys in the 18k gold, particularly copper and palladium, that will have a detrimental effect on its softer, 22k gold neighbour.)

In the end, my clients decided to go ahead with alloying their bands down to 18k white gold. They both wanted matching bands, so his would be 18k white too. The unforeseen bonus to this was we have more material to make a wider band for him too. (After doing a 'test' in sterling silver bands in the equivalent of the amount of 22k gold, his band would only be 3mm wide - so the additional metal was welcome.)

With the decision made to alloy the metal, I purchased the required palladium and silver both of 99.9% purity. Next came the tricky part, how much palladium and silver do I add for a successful 18k white gold alloy? Time to wake up the dormant algebra solving neurons in my brain. (Not interested in the math? Just skip down to the photos!)

First was to determine the composition of the existing rings:

Existing rings of 22k gold = 12.25gms

 Fine gold = 91.67% of 12gms = 11.23gms

Alloy of silver and/or copper = 8.33% of 12gms = 1.02gm

Next to determine the final weight of the future 18k, I used the existing figure of 11.23gms of fine gold as the 75% gold content required and calculated the following. I also referred to Cooksongold's knowledge base to find a suitable general purpose, nickel free 18k white gold alloy. The one I used suggests 11.85% silver and 13.00% palladium. With this 'recipe', I then assumed the existing 1.02gms of alloy in the 22k gold would count towards the 11.85% silver content, and the rest would be palladium.

 

Total weight of future 18k gold (e.g. minimum 75% content)

 = 11.23gms / 75%

= 14.97gms

 

Fine silver to add (e.g. 11.85% content) 

= (Weight of 18k gold  x 11.85%) - existing alloy present

= (14.97 x 11.85%) - 1.02gms

= 0.75gms

 

Fine palladium to add (13.00% content)

= Weight of 18k gold  x 13.00%

= 1.95gms

 

(Since carrying out these maths, I found some very helpful tables in Jewelry Concepts and Technology, by Oppi Untrect, which I used to triple check everything.)

 

Next I weighed out the metals, but not before first cutting out the solder joints from both rings to remove the less pure metals from the equation. The final weight of the 22k gold rings was 12.165gms, from which I made slight adjustments to the silver and palladium weights. Also to be safe, I added ever so slightly less palladium and silver than my calculations revealed just to make sure I didn't dilute the gold content to fall below the 75% required minimum.

 

Photos of the metals used and actual melting I did. I followed the steps as outlined in Harold O'Connor's Jewelers Bench Reference:

Weights of metals before alloying
(Note: 22k gold rings have the solder joints cut out)



Melting the alloy metals first (silver and palladium)

Alloying metals mixed

Adding the gold rings.



Mixing all the metals

Newly alloyed 18k gold in ingot mould.
(Note: Scorfier is still hot, hot, hot!)

Voila! An ingot of 18k gold successfully poured, and ready to be made into two wedding bands.

Actually that last photo was taken a few weeks ago. Since then, I have made her band and taken it to the London Assay office. I am pleased to confirm it was stamped "750", confirming it is 18k gold. His ring was completed this weekend and has a finished width of 5mm. This is 2mm wider than it would have been had it remained 22k.

So in the end, everyone is happy. She has a wedding band that will reside happily against her engagement ring for years to come. He has the wider wedding band he wanted. And, I know how to successfully alloy gold!

Photos of the finished rings can be found here on my website.

VIDEO Lappings, Lemel & Sweeps: A private tour of Hatton Garden

Lappings, Lemel & Sweeps from digital:works on Vimeo.

The history of Hatton Garden in 39 mins! Well, maybe not the whole history, but it definitely packs in a lot about the jewellers and gem cutters of London's most famous jewellery district. And, anyone who is interested is interested learning about Hatton Garden or the jewellery trade should definitely set aside the time, bag of popcorn in hand, and watch it.

A few months ago, I was invited to the private screening of 'Lappings, Lemel & Sweeps' at The Goldsmiths' Centre. It was such a joy to watch. I learned a few things, laughed along the way, and found myself in awe of some of the area's longest serving characters, who were sitting and watching the film alongside me.

The film shows how rich the history of the area is through its wonderful collection of entertaining personalities. From gem dealers to manufacturers alike, they tell their stories. It also touches upon the challenges the area has faced in the recent past (cheaper imports, rising rents, etc.), but trumpets a strong brigade of new contemporary jewellers to uphold the Garden's tradition of creativity, innovation, and local craftsmanship.



'Action!' the digital:works film crew recording in our studio

I thoroughly enjoyed the film, which was both informative and entertaining. It did leave me wanting to know more though, especially with regarding the future of the neighbourhood and the industry born from it...


Should digital:works, or any of the students who helped, put together a sequel, it would be very interested to see how Hatton Garden is adapting to the challenges it mentions. For example, how the manufacturing houses are making way for a new generation of independent designer makers with more craft-orientated agendas. How are the makers adapting their businesses to the new technologies available (or not...)? Are the changing tastes and shopping habits of consumers (wanting locally sourced, ethically driven products) making a difference? Or, how the demographics of the trade are changing - e.g. more multi-nationals, more females, fewer apprenticeships. All of these factors which will undoubtedly shape how Hatton Garden evolve.


In the follow up Q&A, there was strong sense solidarity, and uncertainty, in the audience. Many people were asking: What's next? What can WE do? Do WE rally a group of local businesses? Do WE involve the council in some way to protect the area (which I have later learned, some regulations are already in place - whew!). But, in general, no one seemed to have an immediate answer, but one thing was for sure: WE need to spread the word about the film to raise awareness. Tell people about this film!

And, so I am to whoever will listen. I've tweeted, FB'd, now blogged. I've even used the good of fashioned means of word-of-mouth. 

Thank you to all for reading this post. If you have managed to make it through this far in my text. I promise you the film is much more entertaining. And if you do watch it and like it, please spread the word too!

 

Andy being interviewed (check out the quiff!)

P.S.  I'm also pleased my studiomate, Andrew English, is featured as representing this 'younger generation' holding the torch and leading the way (an Oxy-Gas torch, that is - check him out in minute 34:45). And, I played my own small part in the film by dog-sitting, Hester, our studio Border Terrier during Andrew's interview. At its most crowded, there were eight people in our tiny studio, so the only place for poor Hester to sit, was on my lap - but judging from my photo, I don't think she minded?

Hester, our studio mascot, relegated to my lap during the filming so she wouldn't make any noise during the filming

New Logo!

new ALH logo launched at Christmas 2012

True, it has nearly been a year since I last posted anything, but the good news is this is because I have been busy with my collections, commissions, and also a bit of rebranding. Some of you may have already noticed that I posted a new logo on my website last Christmas. This redesign is thanks to the brilliant collaboration with local design firm, Space Agency Design. The concept was similar to my first attempt - to have my initials abstracted into a something simple that reflected my architectural background. The result is pictured above! I hope people like it and feel it is also a great improvement on my first attempt back in 2009, which was a bit fussy and used an underwhelming colour (below).

Previous logo from 2009.

With a new logo in hand, I have been putting it wherever I can - new packaging, business cards, postcards, posters. My first investment was having new gift bags and boxes foil printed, which I just managed to get done in time for last November's Made in Clerkenwell: Open Studios. (Thank you, Lily, at Potters Ltd for sorting that out so quickly!) I also had new business cards printed from my favourite local printers, Moo,  who incidentally are just over the road in Shoreditch. If I do say so myself, I think my new logo sits nicely alongside the Fairtrade & Fairmined gold dual logo - a very happy accident.

It has been wonderful having a new logo. It might not be my last, but for the moment it feels like a big step for my business. And, being my first blog post in nearly a year, a sort of fresh start into a new routine of posting more blogs to mark other milestones and musings of my business. 

Thank you for reading!

new packaging with gold foil printing

new business cards hot off the press