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.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:70:9 –

And the mountains will be like wool,  

and the mountains will be as flakes of wool, in terms of ˹their˺ lightness and ˹their˺ floating about in the wind.
القرآن:٧٠:٩ –

وَتَكُونُ الْجِبَالُ كَالْعِهْنِ  

{وتكون الجبال كالعهن} كالصوف في الخفة والطيران بالريح.

See similar narrations below:

Collected by Qurʾān
quran:101:5 –

And the mountains will be like wool, fluffed up.  

and the mountains will be like tufts of wool, like carded wool in terms of the lightness with which it floats ˹in the air˺ until it comes to settle upon the earth.
القرآن:١٠١:٥ –

وَتَكُونُ الْجِبَالُ كَالْعِهْنِ الْمَنْفُوشِ  

{وتكون الجبال كالعهن المنفوش} كالصوف المندوف في خفة سيرها حتى تستوي مع الأرض.