Dijon, France/dijon613
Previous | Home | NextThe filtering vat (B) was used for leaching the "ripened" saltpeter bed material. The plug (C) was used for allowing the filtered solution to drain from the bottom of filtering vat (B) into collection vat (D). (This process was repeated if a clear solution was not yet obtained). The solution from vat (D) was concentrated on the hearth (A), then placed in the crystallization buckets (E) and allowed to crystallize on copper sticks inserted in the buckets. The white crystals were then scraped off the copper sticks and collected. Unbeknownst to the early processers, the lime used in the saltpeter hills furnished the calcium which precipitated out carbonates when ashes (potassium carbonate) were added to the filtering vat; the precipitate of calcium carbonate remained in the filtering vat. The final salt solution containing potassium nitrate was scooped up and placed in the collection vat.
