After prolonged use or exposure to air, copper products may darken or turn black due to oxidation. Here are some effective ways to clean copper products and bring back their lustre:

Use toothpaste

Steps:

Apply an appropriate amount of toothpaste to the surface of the copper product.

Gently rub it with a soft cloth or a soft-bristled brush.

Rinse off with clean water.

Dry with a clean soft cloth.

Principle: The tiny particles in the toothpaste can remove the oxidised layer on the surface, restoring the shine to the copper surface.

Use lemon juice and salt

Steps:

Cut a lemon in half and sprinkle it with the right amount of salt.

Rub the lemon on the surface of the copper product.

Rinse it off with clean water.

Dry with a clean soft cloth.

Principle: The acidic content of lemon juice and the abrasive action of salt can effectively remove the oxidised layer on the surface of copper.

Using vinegar and salt

Steps:

Mix appropriate amounts of vinegar and salt to form a paste.

Apply the mixture to the surface of the copper product.

Rub gently with a soft cloth or soft bristle brush.

Rinse off with clean water.

Dry with a clean soft cloth.

Principle: The acidic component of vinegar and the abrasive action of salt can effectively remove the oxidised layer on the surface of copper.

Using Metal Polishing Paste

Steps:

Apply a small amount of metal polish to a cotton cloth.

Rub it repeatedly on the copper surface.

Rinse off with water.

Dry with a clean soft cloth.

Principle: Metal Polish contains ultra-fine abrasive particles, which can treat rough metal surfaces to a mirror effect, remove oxidation layers, and also provide long-term defence against the regeneration of patina and rust.

Soak with Lye

Steps:

Soak copper items in lye water for about 1 hour.

Gently scrub with a soft cloth.

Rinse well with clean water.

Dry with a clean soft cloth.

Principle: Lye water neutralises the acids on the copper surface and removes the oxide layer.

Using Diatomaceous Earth

Steps:

Take diatomaceous earth, oxalic acid and water and mix them into a paste in the ratio of 6:1:4.

Apply it on the surface of the copper product and let it dry naturally.

Rinse it off with a soft cloth and clean water.

Dry with a clean soft cloth.

Principle: Diatomaceous earth has an adsorption and abrasive effect, which can effectively remove the oxidised layer on the surface of copper.

Using Ketchup

Steps:

Apply a small amount of ketchup on a dry cloth.

Wipe the dry cloth over the surface of the copper product.

Rinse off with clean water.

Dry with a clean, soft cloth.

Principle: The acidic content in ketchup removes the oxidised layer on the copper surface.

Precautions

Avoid using hard cloths: Hard cloths tend to scratch the surface of copper products, resulting in scratches.

Thorough cleaning: Be sure to rinse thoroughly with water after cleaning to avoid residue affecting the lustre of copper products.

Dry in time: After cleaning copper products should be dried in time to avoid moisture residue leading to re-oxidation.

With the above methods, you can effectively clean copper products to restore their original luster and beauty.