Reference for Niddah 37:7

האדום והשחור וכקרן כרכום וכמימי אדמה וכמזוג

'BLACK'? LIKE THE SEDIMENT OF INK; IF IT IS DARKER IT IS UNCLEAN AND IF LIGHTER IT IS CLEAN. 'BRIGHT CROCUS COLOUR'? LIKE THE BRIGHTEST SHADE IN IT.<span class="x" onmousemove="('comment',' This is explained in the Gemara infra. ');">⁴</span>

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