Hello,
there is a color "red:3" noticed at http://wiki.contextgarden.net/Colors.
However, the following code doesn't work with color "red:3" specification:
----
\starttext
\showcolor[rgb]
\color[red]{AAA}
\color[red:3]{AAA}
\stoptext
----
So, how it the matter with using "red:3" correctly?