Recycling old jewellery
October 24th 2015
Recycling old broken and undesired jewellery is a great way to get a new piece that you will love to wear. However you should understand some of the additional costs and compromises when compared to using all new materials.
The length of this post should give you a very good idea of how much extra work is involved. The ring I use as an example shows how well things can turn out despite a few obstacles.
Preparing the Gems and Precious metals
When a customer brings me their precious metals and gemstones to use I have to perform the following tasks that are not required when I supply all new materials:
- The gemstones have to be removed from the pieces with the greatest of care so as not to damage them. This can take considerable time.
- The gemstones have to be measured and identified as best I can. (more on this later)
- The precious metals have to be weighed and sorted. Precious metals that I supply come to me tested and marked to the highest of accuracy for both purity and weight.
- The customers precious metals need to be fabricated into a form suitable for manufacturing. Precious metals I supply come to me ready to use.
- The weights and purity of the metal to be recycled has to be recorded at the start and isolated from my materials until the end of the manufacturing process. When I supply the alloys I only have to measure the weight of the finished piece.
In the case of this job the sapphire was unset but the onyx and diamonds had to be removed from the existing rings.
When I work on my bench using alloys that I provide I group the pieces of jewellery into the various different precious metals. This means that whilst a piece of jewellery is either soaking in the acid pickle, in the polish tumbler or some other time consuming process that does not require me to sit there and wait I can continue to work on other jobs without having to clean down my bench to avoid the mixing of different precious metals.
This is the most economical way to work as I don`t have to charge my customers for idle time.
When I work using a customers gold however I cannot mix it with my gold even if it is the same alloy for the following reasons:
- Unused gold needs to be returned to the customer.
- I do not know the source of a customers gold or the authenticity of its hallmark. I can acid test to check for purity but this is a crude and rough test of gold purity.
- Alloys even of the same purity can vary in colour.
The result here is that when working with a customers gold I cannot work on any other piece of jewellery without sweeping down my bench. This decreases the efficiency of my time, and makes a job longer to complete than it would if I supplied all the precious metals.
For this remodel all of the rings were 9ct yellow gold and weighed 16.6 grams in total. Once the Onyx and diamonds were removed the gold weighed 16.2 grams.
The number one thing when using gems supplied by customers is to let them know to the best of my ability what they have. The parti colour sapphire for this job according to my customer was fossicked by a relative and cut locally. It is a very clean gem with almost no visible flaws under 10x magnification and more than likely totally natural.
When I remove gems from pieces I prefer for the customer to be present. Often flaws such as chips can be hidden by the setting. Many times I have removed a gemstone from a piece in front of a customer to reveal a hidden flaw.
Here are some other points about recycling gems:
- Most of the jewellery brought to me for remodelling has been purchased from jewellery chains. Most customers are also not aware of how low the average quality of the gemstones that the jewellery chains sell is. The true quality and size of a gem becomes all too apparent once it is out of the setting.
- Many of the gemstones sold in the world today are treated to enhance colour and or clarity. Some of these treatments/enhancements can be undone by processes used in normal manufacturing. There are usually ways to work around this but many of them add time to the manufacturing process. Bottom line here is that without submitting gems to a laboratory for costly testing I have to assume that all gems that I have not supplied myself are treated and work with them accordingly.
Gemmology is a different profession and often even a gemologist will require expensive equipment to identify gems with 100% accuracy. Identifying a gem is not as simple as just looking at it.
Designing with predefined gemstones
When I design I usually work towards a look that my customer desires. Once I achieve that look I calculate the size of the gems required to create the design and quote. Using pre defined gems that a customer is supplying can make the design process much longer as we try to make gems that are not the right size look the best in the chosen design.
Simply put, designing around predefined materials can be much harder. For this ring the diamonds shown in the digital mockup above were 2mm in diameter and suite well the intended design. However once it was decided to proceed on the design and quote, the diamonds were removed from the scrap ring and we discovered that they varied in size from 2mm to 1.7mm. This variation in sizes forced us to change the above design slightly and we discuss this later.
Subtractive Manufacturing - why you need extra metal
Jewellery is generally created using subtractive manufacturing. We start with a larger form and manipulate and take away from it to create the desired shape. It might be true that a piece of jewellery consists of many pieces that are added to each other (additive manufacturing) but those individual pieces are usually created with subtractive manufacturing.
If we remember that when using a customers precious metals I am not able to mix it with my own, the result here is that the customer needs to supply all the extra gold required for the subtractive manufacturing process. What is unused is returned to them.
This is why despite the ring I was making for this customer being well below 16.2 grams in weight I needed that much to cost effectively create this particular design.
Quality/Purity of the alloy & why not all alloys recycle
Pure precious metals tend to melt and remelt very well...but we make jewellery out of precious metal alloys.
Precious metal alloys such as 9, 14 and 18ct yellow and white golds are created by adding base metals and other different precious metals to pure gold.
These alloys can be adversely affected by repeated melting and working. The more base metal in an alloy and the more times it has been remelted, the greater the chance of the alloy becoming unstable.
The most common fault found in recycling a customers gold is that it looses its ability to be reshaped, it cracks during working. This is a manufacturing risk that all customers must be aware of when recycling their own precious metals.
Most pieces made from recycled low carat alloys such as 9ct yellow gold have some minor problems but there is the chance that the flaws could be more obvious.
White gold alloys generally do not remelt very well and nickel white gold alloys I do not even attempt to melt/rework as they are almost guaranteed to crack.
Unexpected variations in materials
When I quote on a job I often have to estimate materials I have to work with because the customer usually does not want me to dismantle the pieces until they decide to proceed.
If a customer is prepared for me to dismantle the jewellery prior to quoting/designing so that I can get accurate measurements, costs are involved because as mentioned earlier this process takes time.
During the intitial design/quoting process for this ring we estimated that the customers diamonds were about 2mm in diameter with some variation. However once they were unset we discovered that they varied in diameter by about 13%.
This sort of variation I would not tolerate in diamonds sent to me by a supplier for this sort of job as it reduces the appearance of the piece and also complicates the setting.
Given that we were restricted to using the diamonds supplied by the customer we had to change the setting style of the outside claws.
To allow for the variation in size we set the smallest diamonds under the four larger claws of the main gemstone and changed the outside claw style from a single claw to a split claw. This allowed us to bridge the gap between the claws and diamonds that the variation in gem size created. You can see the originally intended single claw in the top half of the photo to the right, with the split outside claw of the finished ring in the bottom half.
The finished piece
The 9ct yellow gold reworked extremely cleanly and I was able to hide pretty well the variations in the diamonds size. The lower quality of the diamonds is what it is and the customer accepts that.
The customer was thrilled with the finished ring. The finished weight of the ring was 4.8 grams. 7% of the gold supplied was not recoverable from the manufacturing process but the remainder shown under the finished ring in the photo to the right was returned to the customer.
So now you know a bit more about what is involved in recycling old pieces of jewellery. It is simply not a case of taking 5 grams of scrap jewellery to remodel into a new 5 gram ring.