Svanbergite is a difficult mineral to classify in that it has both a phosphate anion group and a sulfate anion group. The phosphate anion group would normally dictate that svanbergite be classified in the Phosphate Class of minerals. But svanbergite's sulfate anion is intricate and essential in its structure, while the phosphate anions can be substituted for to at least a limited degree. Some other classification schemes may place svanbergite in the Phosphate Class however. Luster is vitreous to adamantine.
Specimens are mostly translucent to small crystals being transparent.
Crystal System is trigonal. Crystal Habits include pseudocubic rhombohedrons and modified rhombohedrons. Faces tend to be curved and striated. Hardness is 5. Streak is white.