Reference for Niddah 39:14

שחור כחרת ושחור שאמרו דיו

is the colour of ink. Then why was it not directly stated, 'Ink'? — If 'ink' had been stated, it might have been presumed to refer to the watery part of the ink,<span class="x" onmousemove="('comment',' I.e., the upper part above the sediment. This is not so black as the lower part. ');">¹⁰</span>

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