Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
bayhaqi:1553Abū ʿAlī al-Rūdhbārī > Abū Bakr b. Dāsah > Abū Dāwud > Makḥūl al-Nisāʾ Lā Yakhfá ʿAlayhin al-Ḥayḍah

[Machine] Her blood is black and thick, so if that goes away and becomes thin yellow, then she is experiencing menstruation, so she should perform ablution and pray. The Sheikh, may Allah have mercy on him, said, "And the meaning of what Makhooul reported from Abu Umaamah is raised with a weak chain of narration."  

البيهقي:١٥٥٣أَخْبَرَنَا أَبُو عَلِيٍّ الرُّوذْبَارِيُّ أنبأ أَبُو بَكْرِ بْنُ دَاسَةَ ثنا أَبُو دَاوُدَ قَالَ مَكْحُولٌ النِّسَاءُ لَا يَخْفَى عَلَيْهِنَّ الْحَيْضَةُ

أَنَّ دَمَهَا أَسْوَدُ غَلِيظٌ فَإِذَا ذَهَبَ ذَلِكَ وَصَارَتْ صُفْرَةً رُقَيْقَةً فَإِنَّهَا مُسْتَحَاضَةٌ فَلْتَغْتَسِلْ وَلْتُصَلِّ قَالَ الشَّيْخُ رَحِمَهُ اللهُ تَعَالَى وَقَدْ رُوِيَ مَعْنَى مَا قَالَ مَكْحُولٌ عَنْ أَبِي أُمَامَةَ مَرْفُوعًا بِإِسْنَادٍ ضَعِيفٍ