Argentium Sterling Silver

Argentium® Sterling Silver

Whats the worst thing about working with sterling silver? Firescale! This copper oxide is hard to remove at the best of times. You need to pickle, maybe abrade as well to remove deep-seated oxide and the residual copper-rich pink areas from your jewelry. So Hoover & Strong has made this much easier. We now have Argentium sterling silver, a sterling alloy for jewelers and silversmiths who no longer want to deal with firescale. Argentium sterling silver is also heat hardenable, tarnish resistant and has excellent mechanical properties, making all forms of fabrication easy. For a final operation to make your jewelry stronger, heat treat it to achieve hardness values approximately twice that of annealed standard sterling silver. Unlike traditional sterling silver, Argentium sterling silver casts and solders without fire scale. It can also be laser and resistance welded. Argentium is available in sheet, round wire and selected sizing and shape wire profiles.

Annealing: If using a furnace, the annealing temperature range is 1050 to 1150°F (565 to 620°C) with a dwell time ranging from 30 to 60 minutes at temperature, depending on size of the furnace load. If torch annealing, a dull red is the color to look for, but this alloy displays a lighter color when heated, so take care. If the metal looks yellow or light orange, it is too hot.

Increasing the hardness of Argentium: This alloy may be age hardened by annealing at 1150°F for 1 hour followed by a water quench, then aged at 580°F for 1-2 hours. Hardness values of up to 125HV can be achieved – twice that of annealed standard sterling silver. This heat treatment operation will also help improve the tarnish resistance of Argentium.

Polishing: To avoid contamination from other alloys in the workshop environment, it is ideal to have separate polishing wheels for
use on Argentium sterling silver only. If this is not possible, thoroughly rake wheels before use.

Soldering: Because Argentium sterling silver displays a lighter color when heated, a little more care must be taken during heating operations. Low temperature solders are therefore recommended, we recommend solders with flow points below 1400°F. Use our Argentium hard, medium and easy solders for best results because it is important to avoid overheating this metal. Use standard soldering fluxes.

Useful information:

• Density: 10.3 g/cm3 (5.42 troy ounces/in3)
• Melting range: 1410°F - 1610°F (766 - 877°C)
• Hardness values: Annealed: 60 HV — Hard rolled: 110 HV, Age Hardened: 125 HV

Casting Argentium sterling silver:
Use the following information to successfully cast Argentium silver.

• Melt range: 1410°F - 1610°F (766 - 877°C)
• Casting range: 1740 - 1780°F (950 - 980°C)
• Flask temperatures: 950 – 1000°F (510 - 538°C). Do not exceed 1250°F.
• Density: 10.3 g/cm3 (5.42 troy ounces/in3)
• Quench time: 15 minutes minimum to prevent cracking.
• Recycling: We recommend using at least 50% fresh metal with each cast.
• Hardening: If flasks are quenched after 15 minutes, the castings will have the same hardness as standard sterling silver. The hardness of castings can be increased by leaving them in the flask until cold, or by heat treating the whole tree/individual castings in an oven set at 580°F (300°C) for 45 minutes then air cool.