Fusionstone is a material found on Bajor that the Bajorans have used as a building material for thousands of years. It is sometimes sand colored. (DS9 novel: Bajor: Fragments and Omens)

The buildings and thoroughfares of Ashalla were constructed using fusionstone, as were the walls of the Naghai Keep. (DS9 novel: Bajor: Fragments and Omens, TLE - Terok Nor novels: Day of the Vipers, Night of the Wolves)

Fusionstone was used in the cells of the Elemspur detention center, a former monastery. (DS9 novel: Fearful Symmetry)

Fusionstone was also used by the Bajorans of the mirror universe, such as in Vekobet. (DS9 novel: The Soul Key)