Salt and its receptacle date back to Roman times. Salt was expensive and considered a bit of a luxury. In fact the latin word salarium from which the word salary is derived from, meant an allowance of salt made by Romans to their soldiers as part of their salary.
Move onto the medical times and salts had a ceremonial importance identifying a persons status in society. The nearer you were to the large master salts when dining the more important you were. The most significant salts could be real masterpieces made by the finest gold and silversmiths, lesser nobility would often use wood, These large antique treen master salts, which can also be real gems, were made from a number of varieties of timbers and would br placed in front of the master of the house. Lower ranking guests would use salt trenchers much smaller and shallower. Hence where the saying "above and below the salt' comes from.
Interestingly salt is suppose to season wood and certainly with the earlier salts although the foot and stem is often seen with large splits, the bowl suffers less.
In the late 19th century salt began to loose its importance as it became cheaper and more freely available and nowadays with the use of enticing additives in salt the salt cellar has little use to many.
Antique treen salts is an interesting area to collect as there is such variety and mid to late 19th century ones can be found at reasonable prices.
Pictured here are two early salts, the first is an antique treen English master salt from around 1600 and the other is an elegantly turned salt from the early 1700's carved on the base is Coopers Inn London.