It is difficult to distinguish from donnayite and ewaldite with which it often occurs in epitactic intergrowths. Diaphaneity is transparent to translucent. Crystal Habits include complex rounded hemimorphic crystals and spherical aggregates.
Fracture is uneven.
Hardness is 3.5 - 4. Streak is white. Associated Minerals include calcite, chlorite group, donnayite, ewaldite, microcline and natrolite.