Umm Salama (a.s.), that she says, one night the Holy Prophet (S) went away from our midst and did not return for quite a long time. When he came back his hair was disheveled and he was covered with dust and one of his palms was closed. I asked, “O Prophet of Allah! What has happened, for I now see you distressed and covered with dust.” The Prophet replied,
“I was taken to Iraq at a place called Karbala, and was shown the place where my son Husayn and other members of my family and children will lay slain. I have gathered their blood (red sand) and it is here in my hand.”
Then he opened his palm and said, “Take it and preserve it with you.”
I took it from him and saw that it was red colored sand. I kept it in a bottle and sealed it’s lid and preserved it with me.
When Husayn left for Iraq from Makkah, I would remove that bottle every day and night and smell it and look at it and weep over the sufferings, which would befall him. Then on the tenth of Muharram, the day on which Husayn was martyred, I removed it in the first part of the day and it was as usual.
Then when I removed it in the last hours of the day, I saw that it had turned into pure blood. I was grieved and started wailing in my house, but I concealed it, lest the enemies in Madina might be informed of it and may hasten to rejoice over it. From that day onwards I kept this sorrow concealed in my heart until the time and day the news of his martyrdom reached Madina, thus its verity was proved.
Reference : Nafasul Mahmoom – Shaikh abbas Qummi (r.a.)