After the end of the previous harvest season, the ponds are allowed to flood in order to protect the earthen barriers from erosion from rain and wind. In the springtime, normally in March, water is allowed to drain out and the ponds are cleaned and prepared for the harvesting season. Any structural damage or erosion to the pond barriers will be repaired at this time. Accumulations of plant matter and any other detritus are removed.
The process of forming salt out of seawater is effected through the cumulative effect of evaporation due to sun and wind. Thus, fresh seawater needs to be allowed in and consequently evaporated. Water is let in to an initial large pond during high tides. This pond serves as the source of water to the rest of the ponds until the next series of high tides. These high tides usually occur on a two week cycle.
Evaporation area has the function of raising the salt concentration, also allowing the elimination of the excess of some undesirable substances. In order to concentrate the salt water into brine, a successive series of intermediate ponds are used. The salt proceeds from one pond to the next using gravity. The depth of water allowed in each pond determines the strength which the sun can act on the water to warm it. The hotter the water becomes, the quicker it evaporates. The ponds at this stage are large to allow abundant wind flow across the water surface. During this process the degree of salinity of the water increases, almost to the point of crystallization.
Salt Cristallization Water from the evaporative ponds is let into smaller crystallizing ponds. Crystallizing ponds are geometric networks of small ponds around which flows a common source of brine water. These ponds are smaller to aid in the harvest of the salt, which is performed manually using long wooden rakes. Alternatively, flor de sal is harvested off the top of the water using fine nets on wooden poles. Between each small pond is a berm which allows the working of the ponds and also a place for the harvested salt to drain off excess brine water before storage.
Flor de sal is manually skimmed from the top of the water, which is why it is sometimes considered as “the cream on top of the milk”. Flor de sal can only be harvested when the weather is agreeable. Too much wind and the crystals will sink to the bottom turning into coarse salt. The fact that the crystals of Flor de Sal are at the start of their formative process explains their naturally fine and flaky nature. Flor de Sal is harvested into baskets where it is allowed to rest and drain residual water and then stored indoors.
Traditional sea salt (Sal tradicional) crystallises in the bottoms of the saltpans and is gathered by hand every 3-4 weeks. The method and care used in the harvest of the salt has a lot to do with the ability to obtain a good quality salt, a naturally white salt with shiny crystals. Using traditional wooden rakes called 'rodos', the salt at the bottom of the pond is broken up using some light blows and agitation and consequently raked to the sides of the ponds. This needs to be done carefully so as not to reach the earthen bottom. A layer of salt should always be left to insulate the bottom of the pond. The raking process acts as a natural cleansing mechanism for the salt as most impurities are removed by the flow of brine water through the crystals.
The final step of artisan extraction is to leave the salt be dried by the sun. The coarse salt raked to the sides of the pond, is then shaped into piles where it dries in the sun and the wind. This preserves the typical moisture and mineral composition of traditional sea salt. After drying the salt is stored indoor and later it will be manually cleaned, to remove impurities that may be left behind. Flor de Sal is harvested into baskets where it is allowed to rest and drain residual water, before is stored indoors.