[NTG-context] How to obtain blackboard bold?

As in subject;) I found out that {\mb R} gives me the symbol for the real line; is it _the_ ConTeXt way or should I do it in another way? Greets -- Marcin Borkowski (http://mbork.pl) Kim jest ta, co wyłania się z pustyni, Idzie wsparta na swoim Oblubieńcu?