Enigmatic Condenser Coding

[Winky Dink]

Please help me read these caps. I figured out the disk on the right: green-black-red, 5000 pF. The confusing thing was that the Wallace manual said the values for mica and ceramic would be in picofarads, but apparently not in this case. Is there a convention for orienting a disk so you know whether you're reading right-left or up-down?

The ceramic on the left baffles me. If you ignore the violet top and the third black stripe, then it reads 20 pF like the schematic specifies. Are the violet top and third black stripe for voltage, tolerance, or....?



Thanks,
Winky