We welcome you to this edition of United News. As precious metal markets continue to rise, there has been greater consumer awareness in precious metal products as well as the
refining aspect of precious metals. In any event, it is an interesting time for all of us.
In this edition of United News, we bring you tips and techniques to help in your workings with precious metals, as well as information on products and services that maybe of some
interest to you. As always, if you read anything in this edition, or hear of anything else out there that you may need some clarification on, we are here to help.
President and CEO
In this issue of United News …
With the increases in prices of precious metals it is wise to review your recovery procedures to optimize the retrieval of precious metals in your manufacturing operations.
The following are the usual sources of wastes in jewelry manufacturing:
- Melting & Casting
Crucibles, casting dies, molds, slag, flux residues, casting machinery clean up, sweeps from floors.
- Fabrication, Rolling, Wire Drawing, Stamping
Chips around rolling mills and Wire drawing equipment, Particles around stamping and chain making equipment, Lubricating
oils, Rags and wipes, sweeps from floors.
- Assembly, Finishing & Cleaning
Filing, Grinding, Sawing, Soldering, Polishing, Cleaning, Rags and Wipes, Wheels & brushes, Sweeps from floors.
- General Workplace
Smocks and Aprons, Hand washing, Benches, Floors, Walls, Dust on machinery, fans and lights, Sink traps and Rugs.
Typical yields in the jewelry manufacturing
|Type of Material
||Average Gold Content
||39 to 75%
|Bench sweeps & grindings
||19 to 45%
|Sink trap sludge
||0.05 to 4%
|Carpets & wood floors
||0.1 to 4%
|Polishing dust & sweeps
||0.5 to 5%
||0.6 to 5%
|Floor sweeps, emery paper, and brushes
||0.1 to 4%
United stocks different types of containers for shipping in your waste materials, please call us so we can accommodate your needs. We also offer a pick-up service in many areas.
Please check with your United representative for more information.
A simple electrolytic anodizing process can be used to blacken sterling silver jewelry. The process works well on United tarnish and fire scale resistant sterling silver
You will need a rectifier, 2V DC transformer or 2 'D' batteries for a power source. The electrolyte can be a 5% to 7% sulfuric acid solution or 3 to 4 heaping teaspoons of
sodium bisulfate (Sparex 2) per cup of water in a Pyrex container. A small graphite rod (stirring rod) is used for the cathode (-) and a silver hook is used for the anode (+)
to attach the silver item to be blackened.
The piece being blackened should be thoroughly cleaned. The rectifier should be set at 2V DC and the blackening time set to around 2 minutes. While there
should be no bubbling on the silver item during the process, there will be bubbling on the graphite cathode. Rinse and dry the silver item when the blackening process is
If you have any questions or concerns about this process or anything else as it relates to precious metals, drop Doc a note. Doc can be reached at email@example.com. We are here to help.
We at United have a variety of innovative products available to help in your manufacturing and repair challenges.
- United's Sterlium Plus can be used for both casting and fabrication, which makes the product unique in and of itself. Sterlium Plus will provide for greater metal
reusability and superior tarnish resistance.
- United's new 372 White Brass has been formulated to provide greater metal fluidity, which makes the 372 great for award jewelry and recognition products.
- United's Analytical equipment can detect lead and cadmium in jewelry, providing for a safer environment in jewelry production.
Our analytical lab at United is at your service.