graphic
granites with dominant orthoclase the molecular ratio of feldspar to
quartz was about 2:3. In an oligoclase graphic granite the proportion
was about 1:2, and in an albite-quartz micropeg-matite it was about 1:3.
Later Bygdenc
made a considerable number of other analyses of graphic granites with
the special purpose of determining to what extent the quartz-feldspar
ratio is dependent on the composition of the feldspar. He concluded
that the ratio between quartz and feldspar bore no regular relationship
to the composition of the feldspar. He believed that in most graphic
granites definite ratios did exist between the proportions of feldspar
and quartz, but that these ratios were not alwaj-s so simple as Vogt
and Johansson had supposed.
To
supplement the small number of available trustworthy analyses the
writer collected specimens of graphic granite from the Fisher
