For nearly a century gold-black has been recognized as a strong absorber of radiation in the ultraviolet, visible, and near infrared. Early samples of gold-black were formed by milling solid gold into a fine powder. More recently gold-black coatings have been formed by the evaporation of pure gold under vacuum conditions, followed by sublimation of the resulting gold vapor onto a cooled substrate in a chemically inert atmosphere. Gold-black coatings are commonly used in optical and heat transfer applications requiring high absorptivities/low reflectivities. Attempts to model the absorption of electromagnetic (EM) radiation by gold-black have traditionally treated the coating as a homogeneous material endowed with bulk optical properties. Our approach takes into account the actual morphology of the coating, which consists, on the microscopic level, of a tangle of gold trees whose branches and twigs can be modeled as random-fractal antennas. This approach requires a model for the conversion of incident EM energy into sensible heat within a single one-dimensional filament of pure gold. The single-filament model described here is intended to be introduced into a statistical model for the spectral absorptivity of a gold-black layer. The layer model structure will be informed by an SEM-based assessment of the morphology of an actual coating.