No passwords, no registration, no paywalls, no popups, no AI

As an Amazon Associate & eBay Partner we earn from affil links

finishing.com -- The Home Page of the Finishing Industry

Search our quarter-million Q&As

Home of the finishing HOTLINE since 1989

-----

Stains when polishing Argentium

Q. When I cast Argentium after polishing a piece, black stains appears on the surface. I can not remove it pickling or polishing.

Where is the problem?
Adriana Cuellar
AJM - Santa Cruz, Bolivia
2006

A. This looks like fire scale. Most likely your flask was too hot or your melt was too hot or both.
Neil Bell
Albuquerque, New Mexico

That is fire scale, it can be removed with aggressive polishing.
Marc Banks
Blacksmith - Elizabeth City, North Carolina

You can use a chemical solution for cleaning and Ag surface pasivation (to be maintain clean a long period!).
ALEXANDRU SAVU
SC SAVPROD SRL - Bucharest, ROMANIA

Sorry! Finishing.com is temporarily Read-Only.
Ted Mooney is retiring but I have several offers to take it over.
We're working hard to make sure we find it the best new home.

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories: