What is the exact amount of salt that a Rabbi can bless in making Kosher salt?

There is no specific amount of salt that a Rabbi must bless when making kosher salt.

The blessing itself is over the act of making the salt kosher, not the quantity. The important factor is that the salt is properly processed according to the requirements of kashrut (Jewish dietary laws).

Here's what's important for making Kosher salt:

* The salt must be pure and unadulterated. This means it should be free of impurities like dirt, rocks, or other substances.

* The salt must be treated with a "kashering" process. This involves immersing the salt in boiling water for a specific amount of time to remove any potential impurities.

* A Rabbi must bless the salt. This signifies the salt's kosher status and makes it suitable for use in Jewish homes.

The amount of salt blessed in a single instance is not relevant to the kosher status of the salt. The blessing is over the entire batch of kosher salt produced.