Pabstite is a barium tin titanium silicate mineral that is found in contact metamorphosed limestone.

Pabstite commonly occurs as anhedral crystals and masses that vary in their color from colorless to white.

Large amounts of pabstite were found in Santa Cruz as fracture filling and disseminated grains in recrystallized siliceous limestones.

In addition, pabstite can be found in Rush Creek in California when benitoite contains small amounts of tin.

It is commonly occurs in rocks that contain calcite, quartz, tremolite, witherite, phlogopite, diopside, minor amounts of forsterite and taramellite.

Since the silicate rings have a geometry that is identical in all directions, a solid rigid unit is formed in the structure.

The refractive indices of pabstite are ω = 1.685±0.002 and ε = 1.674±0.002 which result in low birefringence and absent dichroism.

[3][5] Pabstite has also been reported from Tres Pozos, Baja California Norte, Mexico and the Alai Range of the Tien Shan Mountains in Tajikistan.