"Saltcake" Crystals

This photo is more for aesthetics and interest than technical perfection. At the plant in which I work, plans are being made to demolish a long ago decommissioned sodium sulphate storage silo. This is what can be found inside. Appartently, water has been seeping (for years?) into the storage vessel, and carrying 'saltcake' from the storage hopper to the grates below and growing these beautiful crystals. It is a shame that they are demolishing it!