Projectile points and other small artifacts chipped from cryptocrystalline silicate minerals constitute a rather difficult photographic problem, for which there is no single solution. Reviews of both photographic and archaeological literature disclose little information on the subject, but show that better photographic methods are badly needed.When the artifacts to be photographed are opaque, dull-surfaced, and of a single color, standard photographic methods, skilfully used, will produce satisfactory illustrations. General discussions of these methods are numerous in photographic literature: a good summary is given in Ridgway's Scientific Illustration.Many small artifacts are translucent at the edges or elsewhere, transparent, multicolored, or have shiny surfaces. Good figures cannot be secured from these by “straight” photographic methods. Several special techniques, largely adopted from other branches of science, will be outlined here.
Color standard for ruby mica
