The earth will consume everything of a person except the tip of his tailbone

It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The earth eats everything of a human being except the lower tip of the spine." It was said: O Messenger of Allah! What is it? He (peace and blessings be upon him) said: "It is like a mustard seed; from it they will be created anew (on the Day of Resurrection)."
This hadith is sahih (authentic) in its chain of narration, but the two Shaykhs (Bukhari and Muslim) did not record it.

It is narrated from Abu Qilabah; he said: A group of Qur'an reciters (scholars of the Qur'an) came to Sayyiduna Abu Dharr (may Allah be pleased with him), and with him was a black woman wearing a Qatawani cloak (of coarse dark cloth); she had neither any fine clothing nor any perfume. Sayyiduna Abu Dharr (may Allah be pleased with him) said: "Do you know what this woman is saying? She tells me to go to Iraq, whereas if I went to Iraq, the people would say: 'This is a Companion of the Messenger of Allah (peace and blessings be upon him),' and they would lavish worldly wealth and goods upon us. And indeed my beloved friend Abu al-Qasim (peace and blessings be upon him) enjoined upon me that the bridge over Hell is a slippery place, and our load is light, so perhaps we will be saved from it."
This hadith is sahih (authentic) in its chain of narration on the condition of the two Shaykhs (Bukhari and Muslim), provided that Abu Qilabah heard it from Sayyiduna Abu Dharr al-Ghifari (may Allah be pleased with him).

It is narrated from Abdullah bin Abi Mulaykah that a man asked Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) about the saying of Allah, the Mighty and Majestic: "And indeed a day with your Lord is like a thousand years of what you count." [Surah al-Hajj: 47] He said: "Who are you?" The man told him that he was a man from such-and-such a place. Then Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: "Then what of the day whose measure is fifty thousand years?" The man said: May Allah have mercy on you! I only asked you so that you would tell us. Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: "These are two days that Allah, the Mighty and Majestic, has mentioned in His Book; Allah knows best about them. We dislike saying anything about the Book of Allah without knowledge."
This hadith is sahih (authentic) on the condition of Imam Bukhari, but the two Shaykhs (Bukhari and Muslim) did not record it. This is the end of Kitab al-Ahwal (the Book of Terrors), and it is the last book of "al-Jami' al-Sahih al-Mustadrak", compiled by al-Hakim, Imam Abu Abdullah Muhammad bin Abdullah bin Muhammad bin Hamdawayh al-Hafiz (may Allah have mercy on him).