In Paradise There are things which no eyes has seen, no ears has heard and no human mind has though of.Prophet Muhammad Sallallahu Alaihi Wasallam
Hajr e AswadAccording to Islamic tradition it holds that the Black Stone fell from Jannah as a proof and guidance to show Adam and Eve where to build an altar the great mosque the prayer place. It became the first temple on Earth. Muslims believe that the stone was originally pure and white, but it has since turned black because of the sins of the people who touch it.
According to Islamic tradition, Prophet Muhammad Sallallahu Alaihi Wasallam, in 605 CE, had set the Black Stone intact into the Kaaba's wall.
About Hajar al-Aswad !
The Black Stone consists of a number of fragments held together by a silver frame, which is fixed firmly by silver nails to the Stone. The present day black stone is a set of smaller fragments that is cemented together to form the seven or eight fragments visible today. The Stone’s measures about 20 centimetres by 16 centimetres. The Black Stone is placed in the eastern corner of the Kaaba, which in Arabic Known as al-Rukn al-Aswad (the Corner of the Black Stone).
Important duties of the pilgrimage and the Umrah is tawaf, Pilgrim begins and end tawaf facing this sacred stone. Throughout the ages, countless muslims including many Prophets (upon them be peace), pious personalities who have performed Hajj and Umrah circled the Kaaba as a part of the tawaf ritual during the hajj and many stopped and kissed the Black Stone, Islamic tradition records it was kissed by Prophet Muhammad Sallallahu Alaihi Wasallam.
For Centuries the silver frame around the black stone and the black kiswah cloth enveloping the Kaaba are maintained by Ottoman Sultans and they are the custodians of the Two Holy Mosques.
Another stone, known as the Hajar as-Sa’adah (Stone of Felicity) is set into the Kaaba's opposite corner, al-Rukn al-Yamani (the Yemeni Corner), at a somewhat lower height than the Black Stone.
Prophet Muhammad (PBUH) said in one of His hadiths:
“By Allah! On the Day of Qiyaamah, Allah will present the Hajar e Aswad in such a manner that it will have two eyes and a tongue to testify to the Imaan (faith) of all those who kissed it.” (Tirmidhi)
Note: That when kissing the Hajar al-Aswad, one should neither push people nor harm anyone because while kissing the Hajar al-Aswad is Sunnah, causing harm to people is a forbidden act (haram).