Goldcoated

Goldcoated refers to a surface that has been covered with a thin layer of gold through a metallurgical process. The coating provides the appearance of solid gold and can offer improvements in corrosion resistance, electrical conductivity, and surface stability while using far less gold than a solid-gold item.

Common deposition methods include electroplating, where an electrical current deposits gold from a bath onto a conductive substrate; electroless plating, which uses a chemical reducing agent to deposit gold without external current; and physical vapor deposition, such as sputtering or evaporation, which create gold films in a vacuum. Immersion plating and related chemical methods are also used in some applications. Coatings can vary in thickness from tens of nanometers to several micrometers, depending on purpose; jewelry coatings are often in the hundreds of nanometers to around 1 micrometer, while electronics may require thinner layers to meet tolerances.

Gold is chemically inert and highly conductive, offering tarnish resistance and biocompatibility in many contexts. However, gold coatings are relatively soft and can wear away with friction, potentially exposing the underlying metal. Adhesion depends on substrate preparation and may involve diffusion barrier or adhesion layers, such as nickel or other underlayers.

Applications span decorative jewelry and watches, electrical connectors and contacts, optical components, and certain medical devices where a durable, low-frriction, biocompatible surface is advantageous.

Care and durability considerations include the possibility of wear revealing the substrate and the potential need for re-plating after significant wear. Plating solutions have historically involved cyanide-based chemistries, underscoring the importance of proper safety measures and waste handling.