Page 87 - My FlipBook

by saturating the brush with the desireil pigment, then varying the thick-
ness of the layer on the paper. The next experiment should be to make
binary combinations. First, red and yellow are mixed in varying pro-
portions, showing orange with a reddish hue and orange with a yellowish
hue. The same experiment is made with red and blue, showing the
variations of the hues of violet from violet with a reddish to violet with
a bluish hue. Yellow and blue are next mixed, showing the variations
in green from a bluish to a yellowish hue.
After the experiments of producing secondary colors by mi.xing
pigments have been completed, the next experiment should be to produce
the same colors by applying a layer of one primary color to the paper,
and, after this has dried, placing the second primary over the first layer.
When the experiments with the binary combinations have been com-
pleted, experiments with the tertiary combinations should be made. Two
primary colors are mixed and the third primary is added in varying
proportions to produce browns and grays. Black can also be made from
the three primary colors by mixing them in proper proportions. At this
time black and white pigments should be introduced ; and the process
of tinting by diluting pigments with white, and saddening colors by the
addition of black, and combining black and white to make grays should
be studied.
After experimenting with water colors, the beginner should carry
on a line of experiments in colors with porcelain. For this work he
should use yellow, blue and dark pink. It has been found that those
manufactured by the S. S. White Dental Manufacturing Company espe-
cially for this purpose are the most satisfactory. While these colors do
not match the primary red, yellow and blue, and do not meet the require-
ments in an entirely satisfactory manner, they enable one to obtain results
that prove that the formation of colors from pigmented porcelain depend
upon the same phenomena of color formation that are involved in the
formation of colors from other pigments.
A suitable mold should be constructed, in which
various combinations can be made. The
'^'^^ be-
method Cf
Cearning to Gombtnc ginner should mold and fuse various combinations
Porcelains. of red, and yellow, and blue in varying proportions.
After studing the phenomena of color tormation in
porcelain, a shade guide for inlay work can be made by combining
porcelain powders in definite proportions.
Dr. V. Walter Gilbert, in his "Notes on Dental Porcelain," offers the
following suggestions to beginners : "The best way for a beginner in
porcelain work, therefore, is to e.xperiment in the mi.xing and fusing of
colors before he attempts the construction of a practical inlay or crown.

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