Three hexes south, one southeast of Alakran.
Tincal is naturally occurring borax salt. In this region, the mineral is piled on the ground and in the south rises in hard, caked hillocks, surrounding a swamp that is near-dry in high summer and watered better in the rainy season. Hardy thorns adapted to the harsh saline soil create a tangled maze of black branches and white crystals.
Is the salt basilisk here because of the borax? Or is the borax a product of this bluish-brown eight-legged reptile's special gaze that turns its victims into salts rather than stone? It's hard to say how many of the saline deposits are the rain-melted remains of victims, lending a poignancy to the potential for profit -- alchemists, tanners, and launderers will pay up to 1 gp/pound for the mineral.
The evidence suggests that the basilisk not only feeds on borax, but uses it to reproduce. At least that is one explanation for why it is licking likely-shaped humps of borax into rough eight-legged shapes. One can only imagine some karmic force reversing years, decades of natrification and turning the finished statue into a young, fresh basilisk as the old one collapses.