Читать книгу Henley's Formulas, Recipes and Processes (Applied Chemistry) - Various - Страница 302

—Aluminum is one of the metals most inalterable by air; nevertheless, the objects of aluminum tarnish quickly enough without being {81} altered. They may be restored to their mat whiteness in the following manner: Immerse the aluminum articles in a boiling bath of caustic potash; next plunge them quickly into nitric acid, rinse and let dry. It must be understood that this method is applicable only to pieces entirely of aluminum.