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stone weight (as used on pickle-tub covers)
weight (as used in balances)
漬け物桶に重石を乗せた。
I placed a stone weight on the pickling tub.
重石の代わりに水を入れた袋を使う方法もある。
There is also a method of using a bag filled with water instead of a stone weight.
梅干しを漬けるとき適切な重さの重石を選ぶのが大切だ。
When pickling plums, pick a stone weight of the right heft.