The word(s) "crumble" appears 3 time(s) in 3 verse(s) in Quran in Muhammad Habib Shakir translation.

(1) And when Musa came at Our appointed time and his Lord spoke to him, he said: My Lord! show me (Thyself), so that I may look upon Thee. He said: You cannot (bear to) see Me but look at the mountain, if it remains firm in its place, then will you see Me; but when his Lord manifested His glory to the mountain He made it crumble and Musa fell down in a swoon; then when he recovered, he said: Glory be to Thee, I turn to Thee, and I am the first of the believers.

(سورة الأعراف, Al-A'raaf, Chapter #7, Verse #143)
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(2) And the mountains shall be made to crumble with (an awful) crumbling,

(سورة الواقعة, Al-Waaqia, Chapter #56, Verse #5)
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(3) Nay! when the earth is made to crumble to pieces,

(سورة الفجر, Al-Fajr, Chapter #89, Verse #21)
(Arabic, Transliteration, Urdu (Ahmed Ali), Urdu (Jalandhry), Farsi, Yusuf Ali, Shakir, Picthal, Mohsin Khan, French, Spanish, Indonesian, Malay, German, Bosnian, Russian, Dutch, Italian, Portuguese, Tafsir - Jalal ad-Din, Tafsir - King Fahad Quran Complex)