There is a BIG difference between class colors and school colors. In the 19th and early 20th centuries, the different classes has different colors, mascots, mottoes, etc. That was not just the case at Tech, but all over the western world. I have seen a copy of that original article, and it clearly said CLASS color, not school color. And the article you provided a link to says that pretty clearly too, although it concludes from that that blue was a school color. My class ring from 1966 also includes a blue stone, because it was the popular available choice, but we never saw blue on the field of play.