Greenockite has the same structure as the zinc iron sulfide wurtzite . The symmetry is broken in a perpendicular direction to the major axis and results in a hemimorphic crystal structure. In other words, there is no symmetry element, like a mirror or two fold rotational axis, perpendicular to the major axis and thus crystal faces on top of the crystal are not repeated on the bottom of the crystal. Crystals of greenockite are typically six sided pyramids where the hemimorphic character is easily seen as the top of the crystal is the point and the bottom of the crystal is the pyramid's base. Often the crystals are platy with a hexagonal outline and the hemimorphic character is then not easily distinguished.
Color is honey yellow, orange, red or light to dark brown.
Luster is adamantine to resinous. Transparency crystals are transparent to translucent. Also seen as crusts or dustings over crystals of calcite , smithsonite and sphalerite . Fracture is conchoidal. Streak is red, orange or light brown.