Mineral ribbons in deposits of volcanic ash ?

Geologists and mineralogists now have another mystery to solve. Bright ribbon-like inclusions are found in boulders at the base of the delta scarp. Such bands can be seen in the laminated ash deposits as well as in lava-like boulders. It is premature to claim that it is Gypsum. That would be a sensation and would mean that it is an evaporite that is formed on Earth with the participation of water.

But now it can be seen that there are pockets in the bright ribbons that are filled with material from the darker layer. This leads to the conclusion that the bright ribbon-like deposits were not formed secondarily. The vertical and horizontal fractures are caused by movements. The reported fibrous structure in the bright layer is an optical illusion.

The rover shot the bright layer with the laser to get a spectrogram. So far the result is not known. It would not be a surprise if it is just a locally occurring variety of ash with another composition.

Bright ribbon in lava ? or ash