Doh! I completely misunderstood it.

That's not even a good rate of return though - barely over 5%. The S&P 500 made over 16% in that same time period. Sure there are fewer zeroes at the end, but millions of regular people made 3x the % increase that Musk did.

It's part of a pair. The other one has three sides with six pips and three sides with two pips. That way you always roll either 7 or 11. They must have gotten separated.