Martin sigma serial number dating
See also the timeline of the Discovery of the Elements Note Some events are grouped together to make it easier to follow a theme. The dates indicate where to find the event in the text. Mesopotamians - (Sumerians, Babylonians and Assyrians) - Bronze Age - Weapons and Tools, Cuneiform Writing, Wheel and Axle, Potter's Wheel, Mathematical Numbering Systems, Calendar with Leap Years, Glass 2500 B. Egyptians, Imhotep - Soldering, Wire Drawing, Architecture, Medicine 2300 B.
The Back Brace Brand: From 1978 through 1983; 1978 being a transition year, one might find the center back brace is pressure stamped, or "branded" in a football shape stating Sigma Guitars/Made in Japan/For/C. During later Korean made years (c1990,) Sigma transitioned back to paper labels and they stayed that way until the end of production in Indonesia in 2007. Adjustable rosewood bridge to approximately 1975, non-adjustable thereafter.
Starting in October 1930, Martin also stamped the model number just above the serial number. Notice the “1” in the “18” does somewhat look like a “2”.
This confuses a lot of people who think their style 18 guitar is a style 28. On round hole martin guitars, the serial and model numbers are stamped on the neck block inside the instrument.
All other text was printed in black ink, or stamped on in ink by the manufacturer (model and serial numbers.) 5-digit, or 8-digit serial numbers. Being a mid-year change, some continued on with the "Purple" label, though with the new serial number designation preceded by an "S" or an "E" This is prefixed by the serial number assigned to the instrument and followed by an ink stamp of the model number. L-R as seen through the sound hole: Serial number, "Brand," Model number.) The serial numbers on these instruments were often preceded by the letters S or E; e.g. It is currently believed that this transition was complete by 1979.
This is especially true of unusual, special (sample/prototype models) and/or low production number models (e.g.: DT-30.) The 'Gold' label: The next generation of labels are transition labels that are white w/Sigma and three horizontal lines in gold ink, the Greek sigma in black and printed black text (Made for C. The Σ symbol now also in this same pink/purple color.