The Salt of the Earth - Ocean Worlds: The Story of Seas on Earth and Other Planets - page 66

fig. 6. Fossilized Miocene seas in the Wieliczka Salt Mine, Poland. St Kinga's
Chapel is hewn from the fossil salt, and is 31 metres long and 15 metres wide.
For everyone needed salt. In the days before refrigerators and plas-
tic packaging and tin cans, salt was needed to preserve meat, fish, but-
ter, cabbage. It was used in tanning leather, in making glass, in making
gunpowder. Rich or poor, everyone needed it. The men who control-
led its supply were the Rockefellers of their day. They wielded true
power, and jealously guarded their privileges. For salt was not easy to
obtain. Winning salt from the sea by evaporation, in salterns, was
long practiced, but slow and cumbersome. An underground supply
of millions of tonnes of salt like Wieliczka, therefore, was better than
a goldmine.
Neither the generations of miners, nor the merchant barons, knew
that the crazily twisted layers of rock salt that they excavated marked
the long, slow dying of a sea, many millions of years ago. That demise,