pigmented colorants: dependence on media and time - Cornell ...

Gamblin Artists Colors Co.; Portland, OR). Note that the media congeals quickly
without constant heat. The author found that an ideal way of working is to use
metal muffin tins on a hot plate for each paint mixture. This keeps the wax molten
to work effectively while combining the pigment-media solution.
Oil. There are many oil-painting mediums in use by artists–typically varying
combinations of oil, varnish and turpentine. Refined linseed oil is the best for
artists’ paint. This linseed oil is of a straw color and is obtained from any art
supply store (Sunnyside; Wheeling, Illinois). Also, a very small amount of Gamsol
mineral spirits is added for consistency.
Tempera. Pure egg yolk, separated from the white is the emulsion for tempera.
To separate the contents of an egg, first cleanly break the shell into two halves.
Carefully alternate the yolk pouch from one half shell to the other, removing as
much of the white as possible. Now, the pouch is rolled dry on a paper towel.
Be careful not to dry the pouch too much, as the skin may catch and break open
unexpectedly. With one hand, pinch and hold the pouch over a jar. As one
punctures the pouch with a sharp tool in the other hand, the yolk will freely run
into the jar. Fresh egg yolk must be used in tempera painting. Hence, paints are
made fresh daily with yolk and a small amount of water.
Watercolor. Gum arabic provides the adhesion for watercolor paints. Crystals
of the substance (Kremer; New York) are combined in a ratio of 1:2 with water.
The gum arabic is left to sit in the water for the crystals to dissolve (1-2 days).
The solution is heated in a double boiler until the solution is completely dissolved.
At this point, the author recommends filtering the solution with cheesecloth to
remove any impurities (i.e. small pieces from the accacia tree). A one-half part
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of glycerin is added as a plasticizer, which keeps the finished paint from becoming