"I do not think "1 G." is a denomination. I believe it may be the engravers initials: I G and not 1 (one) G.

"Newman says these were printed by Anne Catherine Green and Frederick Green. Perhaps "I G." was a son or relative that engraved the plates.

"OR: is "G" an obscure abbreviation for shilling? "1 G." would work if that was the case. If it is, I can find no reference to it."

"IG is the initials of Jonas Green, who was the printer of Maryland paper money when those edge cuts were produced. His wife and sons continued the family business after his death."

"The initials I.G. ("eye gee" not "one gee") stand for the original note printer and newspaperman Jonas (Ionas) Green. He died in 1767 but the printing continued under his widow, Anne Catherine Green and son, Frederick Green. The continuation of his ghostly initials after his death may represent another form of anti-counterfeit "secret mark" started with his earlier notes."

"IG are initials for Jonas Green, Maryland's paper currency printer. IG appeared in the margin of the 1767 two-ninths dollar notes. See the "Colonial Issue of 1770" in this article. (about half way thru the PDF — the pages are not numbered). Jonas died in 1767, but his widow Anne Catherine Green took over the print shop and may have used the same plates for the 1774 issues."

Thanks, everyone! -Editor