Lacus Bonitatis is a small lunar mare

Lunar mare

The lunar maria are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for "seas", by early astronomers who mistook them for actual seas. They are less reflective than the "highlands" as a result of their iron-rich compositions, and...

 that lies to the northwest of the prominent crater Macrobius

Macrobius (crater)

Macrobius is a prominent lunar impact crater located to the northwest of the Mare Crisium. It lies on the southeast edge of the Lacus Bonitatis, a small lunar mare. The somewhat smaller crater Tisserand lies just to the east....

. Further to the north of Lacus Bonitatis is the Montes Taurus

Montes Taurus

Montes Taurus is a rugged, jumbled mountainous region on the Moon. These peaks are located on a highland region to the east of the Mare Serenitatis, in the northeastern quadrant of the Moon's near side. The selenographic coordinates of this range are 28.4° N, 41.1° E, and they have a diameter of...

 mountain range.

This mare is an irregular region of basalt

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic lava

Lava

Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

 with uneven borders. The mare lies within a diameter of 92 km and the longest dimension trends from the southwest to the northeast. The selenographic coordinates of Lacus Bonitatis are 23.2°N 43.7°E.