Matsya Purana 256.16

256.16

stambhasūtrādikaṃ tadvacchubhāśubhaphalapradam.
ādityābhimukhaṃ rauti śakuniḥ puruṣaṃ yadi .. 256.16

Vâstu should never be designed by nails, weapons, leather ashes, burnt wood, bones of horns skulls etc It is most inauspicious to do so with these things It brings in grief and calamities At the time of entering the house the artisan is to make these especially things all the auspicious ceremonies laying out of thread and fixing of pillars etc, is to be done—14 15

When an evil omen occurs eg a vulture shrieks, facing the sun or it touches some part of the body of the owner, it is to be understood that on the corresponding portion of Vâstu underneath it there is the bone of an elephant or of a terrible carnivorous animal, indicating danger—16-18.