What characteristic is unique to the design of Italic calligraphic letters?

The unique characteristic of Italic calligraphic letters is their slanted presentation. This distinctive feature sets Italic apart from other styles of calligraphy, giving it an elegant and flowing appearance. The slant is typically created by tilting the letters to the right, which provides a sense of movement and dynamism. This design choice reflects the historical influence of humanist script, allowing for a more expressive and stylistic approach to letter formation.

In contrast, block structure refers to a style that is more angular and rigid, which is not representative of the fluid nature of Italic lettering. Rounded edges can be found in various calligraphic styles but are not a defining characteristic of Italic specifically. Monochrome style, while it may apply to many calligraphic works, does not uniquely define Italic design, as other calligraphic forms can also be executed in a single color. The slanted presentation is what truly captures the essence of Italic calligraphy, making it a recognizable and celebrated form.