Heres a reference "chart" for different color values for 
Tribes 2 (for things such as particles):

1 0 0 = red 
0 1 0 = green 
0 0 1 = blue 
1 0.5 0 = orange 
1 1 0 = yellow 
1 0 1 = purple 
1 1 1 = white 
0 1 1 = cyan 
1 0.5 0.5 pinkish sort of color (havnt tried it) 
0.5 1 0.5 = pale green 
0.5 0.5 1 = pale blue 
0 0 0 = black (invAlpha must be set to true) 
1 0.5 0.5 = pale yellow