Anas bin Malik reported,

Abu Talha proposed marriage to Umm Sulaym. She said, "By Allah, a man like you, Abu Talha, is not to be turned away, but you are a disbeliever and I am a Muslim woman. It is not lawful for me to marry you. If you accept Islam, that will be my dowry, and I ask you for nothing else."So he embraced Islam, and that became her dowry.Thabit said, "I have never heard of a woman whose dowry was more noble than that of Umm Sulaym, which was Islam itself." He then consummated the marriage with her, and she bore him children.

أخبرنا محمد بن النضر بن مساور قال أنبأنا جعفر بن سليمان عن ثابت

عن أنس قال

خطب أبو طلحة أم سليم فقالت والله ما مثلك يا أبا طلحة يرد ولكنك رجل كافر وأنا امرأة مسلمة ولا يحل لي أن أتزوجك فإن تسلم فذاك مهري وما أسألك غيره فأسلم فكان ذلك مهرها قال ثابت فما سمعت بامرأة قط كانت أكرم مهرا من أم سليم الإسلام فدخل بها فولدت له