Dinosaur Egg salt
In the Philippines, Boholano asín tibuók can only be produced from December to May due to fluctuations in seawater salinity. It's made by soaking coconut husks for several months in oceanside pits continually filled with seawater during the tides.
The husks are cut into small pieces, dried, and burned to ash over the course of a week. The ashes are collected into a funnel shaped bamboo filter and seawater is poured through this to leach out the salt. The brine is collected into a hollowed out coconut trunk.
Then, the brine is boiled in clay pots hung from the walls of a furnace and topped up fresh brine as the water evaporates. Eventually the pots crack revealing a solid mass of hot salt. This salt is sold along with the broken clay pot.
To use the salt, grate a bit over your food. It has a smoky flavor.
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