what media should I use
by Erin
(Vermont)
Hi, I make sterling silver jewelry, and was wondering what media is used to harden sterling? and how long to leave it in? Also, would doing this make it harder to scuff or scratch?
Thanks,
Erin
Stacy's Answer:
Hi Erin!
Tumbling only slightly work-hardens the surface of the metal. For finer wire items, you'll notice more of a difference than with thicker gauge items. I recommend stainless steel shot, water and dish-soap. This medium is used to polish the metal, not scratch it up.
You can harden Sterling and Argentium silvers with a heat treatment. For Sterling silver simply heat it to 600 degrees F (316 degrees C) for 30-50 minutes. A kiln will probably be necessary for this. Air cool the metal before pickling it. The hardness will then be equal to the hardness achieved by cold-working to a 50% reduction or 3/4 hard. For Argentium, place the item on a soldering brick and put into a pre-heated 500 degree F (260 degrees C) oven for 3 hours. Remove, cool completely and then pickle to remove discoloration. That can be done in your kitchen.
Some gemstones may be damaged by those temperatures so make sure to check before heating.
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