Central Meridian: A straight line.
Meridians: Complex curves connecting points equally spaced along each parallel and concave toward the central meridian.
Parallels: Concentric circular arcs spaced at true distances along the central meridian, centered on one of the poles.
Symmetry: About the central meridian.
This is an equal-area projection. It is a Bonne projection with one of the poles as its standard parallel. The central meridian is free of distortion. This projection is not conformal. Its heart shape gives it the additional descriptor cordiform.
This projection was developed by Johannes Stabius (Stab) about 1500 and was promoted by Johannes Werner in 1514. It is also called the Stab-Werner projection.