Hello, I have a strange one...many years ago, I was shooting in a league with cast in a .30-40 Krag.  The lubed bullets, after some months, would show green stain in lube around gas-check.  I noticed same green stain in old Lyman 45 with brass seal.  On some ctgs. left loaded for years, same green at case mouth..but brass not damaged..not pitting, or copper-colored discolaration.  The lube I was, and still use is 40% pure Besswax, 35% Synthetic Spermaceti wax..(from Charley Dell), 15% Anhydrous Lanolin, 10% Castor oil.
Now, when this green stuff was going on...My basement was not being protected 100% by de-humidifier..older model, that would freeze up, so humidity was higher.  For the past several years, I have non-freeze type and humidity levels quite low year around...I have not seen the green since.  Could this have been from the Anhydrous Lanolin..Re-hydrating?  I can't think of anything else in mix that would do it.  Also, with the Syn. Spermaciti..no matter how litttle I add...bulllets sparkle..like crystals in lube..Kind of pretty!  Accuracy fairy dust?  Does anyone else use this Syn. Spermaciti?  Where can you buy it now?  Thanks guys!

.22-5-40 (Thuer breath) ... believe we covered your issue in this thread on The Open Range
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PS: You never did identify the wax that you call  - Synthetic Spermaceti  

40 Rod - what is Spermaceti 116?  Since whale oil and Spermaceti have been banned, the closest double hydro carbon chain waxes available that emulate the wax are jojoba and meadowfoam waxes 

I believe the green color is verdigris, an oxidized form of copper. some element in the lube is breaking down into fatty acids which are attacking the brass. This color appears when copper alloys are weathered, or exposed to seawater, or certain acids.