Transformation (Istihala)

196. If a Najis thing undergoes such a change, that it assumes the category of a Pak thing it becomes Pak, this process is called Istihala; for example, if a Najis wood burns and is reduced to ashes, or a dog falls in a salt-marsh and transforms into salt, it becomes Pak. But a thing does not become Pak if its essence or category does not change; like, if wheat is ground into flour, or is used for baking bread, it does not become Pak.

197. Urn or similar things which is made of Najis clay, is Najis. Similarly, the coal derived from Najis wood, is Najis.

198. A Najis thing about which it is not known whether it has undergone any transformation (Istihala) or not, remains Najis.

199. Any liquor which becomes vinegar by itself, or by mixing it with things like vinegar or salt turns into vinegar, becomes Pak.

200. Wine which is prepared from Najis grapes etc., or if any external Najasat reaches it, as per precautionary measures, if it turns into vinegar would not become Pak.

201. Vinegar which is prepared from Najis grapes, raisins and dates, is Najis.

202. If tiny stems and stalks from grapes or dates are there, and then vinegar is poured over it, there will be no harm, and will become Pak after grapes ferments. Since, some believe that the stem will remain Najis, but considering it Pak it better.