(Mine is black.)
Flow Chart: a graphic representation of what effects what sections of the S-6
I bought one of these years ago for $100 at a rummage sale. A friend told me Hammond organs where "classics" so I got it not knowing what I was getting.
When I got it home I plugged in it's decaying power cord (a few *sparks* here) and turned it on. I was disappointed to find that half the stops did not do anything (Solo section doesn't work) but it did produce some spooky tones that I found interesting and the chord section worked so I was happy.
It turns out it is considered to be unprofessional and unusable by "serious" organists.