gem

A coin of exceptionally high quality, typically considered MS-65 or PF-65 or better.

german silver

An alloy of copper, nickel, and zinc, with a silvery appearance.

Gold Certificate

Note from $10 to $10,000 issued in large-size and small-size formats, redeemable in gold coins. The backs of large-size notes were printed in gold color (and in green for small-size notes).

grade

Designation assigned to signify the amount of wear or circulation a note has experienced and its condition today (see the introduction for more information). Grading can be expressed by adjectives (such as Good, Extremely Fine, and Uncirculated), or by abbreviations in combination with numbers from 1 to 70 (adapted from the coin grading system), such as EF-40 or Unc-63.

grade risk

The financial risk a purchaser takes on when buying an uncertified coin at the price point of its assumed or estimated grade. Should that coin actually be of a lower grade than that originally estimated, the purchaser would not be able to recoup their initial investment.

Grand Watermelon Note

Numismatic nickname for the $1,000 Series of 1890 Treasury Notes (Coin Notes), with three zeros on the back in the form, fancifully, of watermelons. Also see Watermelon Note.

Green Eagle Note

Numismatic nickname for a Series of 1918 $1 Federal Reserve Bank Note with an eagle printed in green on the back.

greenback

Piece of paper money of $1 face value or higher with the back printed in green. Unofficial popular term for United States paper money in general, popularized by the Legal Tender Notes of the 1860s with their green backs (though these were not the first to be printed in this color), and widely used since.

GSID

Greysheet identification number, a unique ID for each coin and paper-money listing in the Greysheet database.