MYSTERIES OF THE EQUILATERAL TRIANGLE - HIKARI Ltd

88 Applications
Figure 3.14: Maxwell’s Color Triangle [5]
Application 14 (Maxwell’s Color Triangle). The Maxwell Color Triangle
[5] is a ternary diagram of the three additive primary colors of light (red (R),
green (G), blue (B)).
As such, it displays the complete gamut of colors obtainable by mixing two
or three of them together (Figure 3.14). At the center is the equal energy point
representing true white. This triangle shows the quality aspect of psychophysical
color called chromaticity which includes hue and saturation but not the
quantity aspect comprised of the effective amount of light.
Application 15 (USDA Soil Texture Triangle). The Soil Texture Triangle
[72] is a ternary diagram of sand, silt and clay which is used to classify the
texture class of a soil.
The boundaries of the soil texture classes are shown in Figure 3.15. Landscapers
and gardeners may then use this classification to determine appropriate
soil ammendments, such as adding organic matter like compost, to improve
the soil quality.
Application 16 (QFL Diagram). Clastic sedimentary rock is composed of
discrete fragments (clasts) of materials derived from other minerals. Such rock
can be classified using the QFL diagram [79].
This is a ternary diagram comprised of quartz (Q), feldspar (F) and lithic
(sand) fragments (L). The composition and provenance of sandstone is directly
related to its tectonic environment of formation (Figure 3.16).