"In NY (COMEX) their were only 5 hours in the trading day (5 one hour brackets) (A, B, C, D & E). The first available letter for month code is F."
"Red Sales were so called because the 13th month and forward were written on the black board with red chalk - hence current color coding years in Chicago long-term fixed income. The Coffee and Sugar Exchange used yellow chalk and they called these trades yellow, e.g., Yellow September."
If anyone wants to dispute these explanations I'd love to hear about it. However, one frustrating thing is that I've had people dispute things I know with absolute certainty that are true based upon what I saw and used myself so if anyone is going to dispute things then make sure your memory is correct. Any and all criticism is welcomed though, info 'at' tradingpithistory.com