Do you know how pure Red looks? What if red has components of orange or violet? How about pure Blue? What if blue has components of green or purple?
We recommend that if you are serious about learning color, you get good quality color standards that designate hue, tone and saturation.
Describing what we see
Core to the system is the hue, which is designated by a letter such as Red, Blue, Green, etc.
Another hue designation written as a prefix acts as a modifier. As an example, OR would mean "Orangy Red"
Then if we prefix our OR with another modifier such as a [-] or [+], we can relate the strength of the secondary hue. An example might be +OR, which would mean "strongly ornangy red" .. or -OR which would be "slightly orangy red".
Those who are exceptionally skilled at discering color components might even use ++OR which would indicate "very strongly orangy red".
And, quite naturally, the position of the secondary component letter designation determines which is the primary hue and which is secondary.
Example: GB would mean "greenish blue", while BG would mean "bluish green".
Some stones will have such a pure hue that the only designation required is the letter, such as the spinel pictured above that could simply be described as R.
When the color description is combined with saturation, tone and grading designation, the resulting system can be very powerful.
It is an easily understood system that can be written in "long hand" or "shorthand" and be quickly communicated.