after further research it looks like

Numbers one to nine:
Alpha, Beta, Gamma, Delta, Epsilon, Digamma (anchient ruin = [ = 60 ), Zeta, Eta, Theta

Numbers ten to ninety:
Iota ( equals 10) , Kappa, Lambda, Mu, Nu, Xi, Omicron, Pi, Qoppa

It appears that G1 has the Greek Numerals/letters Digamma and Iota (F and I) or (60 and 10)

Digamma seems to have something to do with fractions as well??? any ideas?

* the Digamma [ is showen at this address:
http://asgle.classics.unc.edu/numerals/gnum_forms.html

It is noteworthy that the early form of the letter(F)does not appear as a numeral in Attica and very rarely elsewhere, and that the Athenians did not use form [ at all.

* on another site it shows Sigma as equal to [ so this is going to be confusing???