Corrosion refers to the gradual degradation or deterioration of metals caused by chemical reactions with environmental elements such as moisture, oxygen, and various chemicals. This process results in the formation of oxides or other compounds on the metal surface, often compromising the metal’s appearance, strength, and structural integrity.
Process
Corrosion occurs when metals react with substances in their environment. For example, iron reacts with oxygen and moisture to form rust (iron oxide), while silver reacts with sulfur-containing compounds in the air to form tarnish (silver sulfide). These reactions typically occur more rapidly in the presence of moisture and salts.
Types of Corrosion
Oxidation
The most common type, where the metal reacts with oxygen to form an oxide layer. Examples include rust on iron and tarnish on silver.
Galvanic Corrosion
Occurs when two different metals are in electrical contact in the presence of an electrolyte, leading to accelerated corrosion of the more reactive metal.
Pitting Corrosion
Characterized by small, localized areas of corrosion, leading to the formation of pits or holes in the metal.
Crevice Corrosion
Occurs in confined spaces where the environment becomes more aggressive, such as under gaskets or seals.
Impact on Jewellery
Corrosion can significantly affect the appearance and durability of jewelry. Tarnish on silver, for instance, dulls its shine and can be difficult to remove. Rust on base metal components can weaken them and lead to breakage.
Prevention and Care
Material Choice
Using metals that are resistant to corrosion, such as platinum, gold, and titanium, can help prevent corrosion. These metals do not react easily with environmental elements.
Protective Coatings
Applying coatings such as rhodium plating on white gold can provide a protective barrier against corrosion.
Proper Storage
Keeping jewellery dry and storing it in anti-tarnish bags or boxes can help minimize exposure to corrosive elements.
Regular Cleaning
Routine cleaning with appropriate methods and solutions can help remove any early signs of corrosion and maintain the metal’s appearance.
Corrosion is a natural process that can affect the longevity and appearance of metal jewellery. Understanding how to prevent and care for your jewellery can help preserve its beauty and value over time.