Mosaic sextant

It adds a patch to a larger graphic. The upper-right, middle-right and lower-left cells are filled; gaps show the background.

Teletext sent text and simple graphics to TVs in the UK from the early 1970s, using 2×3 mosaics. Similar blocks let early computers plot low-resolution pictures in text. The Unicode proposal called the six-cell tile a “sextant,” by analogy with earlier four-cell “quadrant” blocks, and encoded the set to preserve legacy graphics. Teletext controls could join cells or add narrow gaps without changing the pattern.