We welcome you to this edition of United News. With gold & silver markets continuing to climb, the cost to manufacture
jewelry has increased considerably, which affects both the manufacturing as well as the refining side of business. Our technical
support team at United has become more valuable than ever as these markets soar upward.
Browse our newsletter for cost saving hints that may be able to be applied to your situation. 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 …
We have run across this problem of gas porosity a number of times in hot humid and rainy weather. A customer will
call about a sudden onset of gas porosity in all their castings. We often ask how the weather has been since the problem
started. If the weather has been very rainy or hot and at the same time, extremely humid, a burn out problem is the most
likely cause. The root cause of the problem is smoke from the burning waxes is not venting properly due to the high density
of the warm moist air holding it in the oven. The un-vented smoke creates a reducing atmosphere (oxygen poor) inside the oven.
The calcium sulfate binder in the investment will decompose in reducing atmospheres and release sulfur compounds. The sulfur
compounds will form sulfur dioxide gas in contact with the hot molten metal and be taken into the metal causing SO2 porosity.
Symptoms and signs – gas porosity in all the castings, black soot around the door of the oven or inside the oven, often a
rotten egg smell in the oven or the investment, a gray or yellow color in the investment near the castings.
The cure – Leave the A.C. on during the burn out times (usually at night) as it will reduce the humidity and /or a stronger
venting and air make up in the burn out area. Very often when the wet, humid weather does end, the gas porosity will go
We take great care here at United to process your lots quickly and accurately. By keeping a few of these tips in mind, you will
get the optimum results from your lot.
- Try to always keep your Gold scrap; Platinum scrap and Silver scrap separate, as it will speed up your return.
- Run a strong magnet over your scrap or bench sweeps as it will remove iron or steel materials such as tool pieces, steel
shot, screws, staples or other magnetic materials from your precious metals.
- Weigh and label your scrap precious metals on the individual containers and include the type of material and weight on
your packing list. If any weights are off when we weigh them in on receipt we will contact you before proceeding with
If you have any questions or concerns about your lots or anything else for that matter, please let us know.
United provides stone removal services for your scrap or surplus inventory. This is a chemical process that
dissolves the precious metal and recovers the Diamonds, Moissanite, CZ's along with other harder heat and acid resistant
gemstones. The gemstones are returned to you and we pay on the precious metal content of the metal like any other
refining lot. This process we have at United is much easier and safer than your own removal by hand, especially with
smaller gems. Recycle those old diamonds into new jewelry!
We at United have a variety of timely products available to help in your manufacturing and repair industry challenges.
- Platinet: Platinum based Sterling Silver grain that provides superior hardness and a brilliant white color. This
all-purpose sterling also works well for stone in place casting.
- #341 Casting Bronze: The #341 antique bronze is the newest member of our casting brass and bronze line. It offers greater
metal fluidity and a traditional yellow color with brownish undertones.
- Solders: Did you know that all our solders are cadmium free, which is great for the health and well-being of each and
every one of us? As an additional service here at United, we can also stamp your company name or logo on your solder order.
Please contact the United sales department for further information.