I did present facts (at least they were presented to me as facts)

Fact #1 there was a Diamond C Club in Los Angeles
Fact #2 these chips were delivered to Los Angeles
Fact #3 the last name of the owner of the club began with the letter "I"
Fact #4 the "I"s have a "diamond" shape at the top and bottom.

The question is: are these enough facts to reasonably make an attribution.

What about the Thunderbird chips? How about the Pal's club and Sphinx attributions. Are these attributions rock solid? These circumstantial attributions have been done many times before.

The only "fact" in dispute, for me, is the dates. My note says early 1930s, whereas the chips were delivered in the 1920s.