The Colorant Key & Field Guide comprises a series of interactive tools designed to support the reading and translation of multispectral images. The main feature being the colorant key, which aids in the grouping of colorants based on their shared, average responses to visible light, ultraviolet radiation, and infrared radiation, as expressed in multi-band imaging techniques as ultraviolet reflected (UVR 320-400nm), ultraviolet induced visible fluorescence (UVF 420-680nm), visible (VIS 400-680nm). infrared reflected (IR 830-1100nm [850 peak]), and visible induced infrared luminescence (VIL 830-1100nm).

By employing standardized vocabularies and quantitative metrics such as scene-referred imaging, CIELAB, and the Munsell color system, the tools provide reproducible and communicable results across institutions. The key is not designed to offer definitive colorant identification and does not account for factors such as binder-pigment interaction, admixtures, or layering. It is a guide intended to support multispectral literacy, and to suggest actionable next steps following the reading of images—indicating, for example, whether further analysis might be warranted with XRF, Raman spectroscopy, or alternate imaging methods. This directed approach minimizes the trial-and-error phase by narrowing down the list of potential analyses, thereby saving time and resources.

An important distinction to make is that while XRF produces elemental signals to aid in identification of the makeup of colorants etc., MSI produces a spatial distribution of optical responses. Depending on wavelength and illumination geometry, those responses can relate to absorption, reflectance, scattering, luminescence, translucency, gloss, surface roughness, and relief. Geometry is a strong component of MSI. Changing the relationship between illumination, surface, and camera can deliberately emphasize differing aspects of materiality that XRF and Raman cannot. 

The step-by-step nature of dichotomous keys helps in managing cognitive load by breaking down complex classification tasks into smaller, more manageable parts. Each step requires the user to retrieve and apply previously learned information, reinforcing neural connections and promoting a deeper and more organized understanding of colorant response.

Any information included that has been cited from other sources is not following the standardized vocabularies or value references as described in the INFO section.