The term "salt a mine" refers to the act of sprinkling salt onto the floor of a mine to prevent explosions. However, there are several synonyms for this term, each with their own unique history and usage. One such synonym is "salting the pit", which was commonly used in the 19th century during the California Gold Rush. Another synonym is "blessing the mine", which has religious connotations and was popular in the mining communities of medieval Europe. Yet another synonym is "preparing the shaft", which is a more general term that can refer to any type of mining preparation, not necessarily related to salt.