Laws of Impurity in Items Similar to Earthenware.
This question and answer were automatically translated using our trained AI and have not yet been reviewed by a qualified rabbi. Please treat this translation with caution.
go to original →
Question
In the laws of impurity, earthenware vessels become impure. What is the law regarding other materials similar to earthenware, such as cement and plaster, etc.? Are they considered like earthenware? Is the definition of earthenware a specific type of clay, or any type of sand from which an impure vessel can be made? Perhaps it depends on the manufacturing process: earthenware is made from clay that is fired in a kiln, cement hardens without a kiln, clay sold today in stores is fired in an oven at 1400 degrees, plaster hardens but dissolves in water. Glass, as is known, becomes impure only by rabbinic decree, although it is also made from a certain sand, but the process is different: glass sand is placed in an oven, and at 1000 degrees it softens and can be formed into vessels.
Answer
Shalom and a good week
Some of the early authorities hold that there is no difference regarding impurity between vessels made from earth that is fired in a kiln and earth that dries naturally, and in both cases, they do not become impure. Others differentiate between those fired in a kiln and those not fired.
Source
Keilim Perek 10 Mishnah 1.