This hypercompact hyperbolic tesselation uses the thet in the sense of an infinite bollohedron as one of its cells.

Incidence matrix according to Dynkin symbol

o3o3x7o   (N,M → ∞)

. . . . | 14NM |    6 |    6   3 |   2  3
--------+------+------+----------+-------
. . x . |    2 | 42NM |    2   1 |   1  2
--------+------+------+----------+-------
. o3x . |    3 |    3 | 28NM   * |   1  1
. . x7o |    7 |    7 |    * 6NM |   0  2
--------+------+------+----------+-------
o3o3x . ♦    4 |    6 |    4   0 | 7NM  *
. o3x7o ♦  21M |  42M |  14M  6M |   * 2N