(n.)
In heraldry, azure is the color blue. It is typically (but not always) a deeper shade of blue based on the precious stone lapis lazuli, the name from which the word “azure” is ultimately derived.
On coins, medals, and other numismatic items, azure is an element of iconography, represented by horizontal bar shading. It is not (typically) colored blue with paint or other pigmentation. An example of this use is the horizontal bar running across the top of the Union shield found on U.S. coins like the Type 1 American Silver Eagle or on the reverse of the Liberty Head half eagle in the image above. Another excellent example is on the two-cent piece.
See also LANǴUED, another heraldic term for a figure (usually an animal like an eagle or a lion) with its tongue visible.
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I have a few Lincoln pennies that have the L in liberty crowded into the rim of the coin and iberty only shows. Also have few with the D for Denver mint completely over stamped or filled in and looks like a blob. A penny with a double node inside the 0 where one cent is. Are these worth anything
@Paul Fletcher: I can’t speak for the O in ONE CENT, but the other two cases sound like normal minting variations. As we’re all familiar, for decades the Mint struck huge numbers of cents on high-speed presses. That allowed for more die wear and other vagaries than might be found on other denominations.
In particular, for a few years the hubs that are used to create dies had become quite worn and started to spread. In addition to blurring portraits and other images, it forced legends closer to the coins’ edges – which is exactly what you’ve described with “IBERTY”.
High-speed production made it somewhat more likely that a bit of grease or other foreign material could get into the incuse recesses of a die that strike a positive image on a coin. If the material affects a character with a center hole (O, 6, D, etc.) it can turn the letter into a little blob. Such “filled die errors” can be interesting, but not very valuable on a coin produced in high numbers. That said, I’ve talked to niche collectors who’ve made curious sets of type coins with filled die errors in different characters.