This specification establishes the requirements for electrodeposited gold coatings for engineering applications, employed specifically for their corrosion and tarnish resistance (including resistance to fretting corrosion and catalytic polymerization), bondability, low and stable contact resistance, solderability, and infrared reflectivity. This specification does not cover gold coatings produced from autocatalytic, immersion, and vapor deposition. Coatings shall be classified into types, which characterize minimum purity, and codes, which designate Knoop hardness. Coatings shall be sampled, tested and conform to specified requirements as to purity, hardness, appearance, thickness, mass per unit area, ductility, adhesion (assessed by either bend, heat, or cutting test), and integrity (including gross defects, mechanical damage, and porosity).