Rif Kiddushin 6a {19b; 19a; 12a - b}

{Kiddushin 19b}
And if not, she is not betrothed. It is an allegory to one {=the first one} who says to a woman "behold you are betrothed to me from now, after 30 days," and another one comes and betroths her within those 30 days, that she is betrothed to the first one.

{Kiddushin 19a}
Rava cited Rav Nachman: A man may say to his minor daughter "go and accept your {money for your} betrothal," from that of Rabbi Yossi bar Yehuda. For Rabbi Yossi bar Yehuda said: The first moneys {for the Hebrew maidservant} are not given for betrothal, and if he leaves over of it the value of a perutah, it is a valid betrothal. So too here, there is no difference.

And Rav Nachman said: If one betroths with a loan which has upon it a pledge, she is betrothed. Does not Rabbi Yossi beRabbi Yehuda say that "the first moneys are not given for betrothal," and it is a loan and she herself is the pledge, and where he leaves over the value of a perutah, it is a valid betrothal. So too here, there is no difference.
*)

{Kiddushin 12a}
"With money -- Bet Shammai say 'a dinar or something worth a dinar', etc.":
They learnt {in a brayta}: Six silver maah in a dinar. A maah is 2 pondions. A pondion is 2 issars. An issar is 2 mesames. A mesames is 2 contriks . A contrik is 2 perutot.
Thus, it comes out that a perutah is 1/8th of an Italian issar. And a seorah is 1/192 of a Shashrang zuz, and this is the gold dinar of the Arabs. Thus, it comes out that a perutah, based on this measure, is 1/2 a chakah. For the gold dinar is 96 chakah.

Shmuel said: If he betrothed her with a date, even if a kur of dates cost a dinar, she is betrothed. For we worry that perhaps it is worth a perutah in Media.

But we learnt {in the Mishna}: For a perutah or the value of a perutah?

This is no question. There {in the Mishna} it is dealing with certain betrothal. Whereas here it is doubtful betrothal.

(* There was a certain man who betrothed with a bluish marble. Rav Chisda sat and assessed it, whether there was in it the value of a perutah or whether there was not in it the value of a perutah.

{Interjection:} Why did he do this? But Shmuel said that we worry!?
Rav Chisdah did not hold like Shmuel.

The mother of the bride said to Rav Chisda: At that time that he betrothed her, it was worth a perutah.
He said to her: You do not have the power to make her {=your daughter} forbidden on the later one {second groom}.

{Kiddushin 12b}
Is this not like Yehudit, the wife of Rabbi Chiyya. She had pain in childbirth. She {=Yehudit} said to him {Rabbi Chiyyah}: My mother told me "your father accepted on your behalf {money for} betrothal when you were young." {Therefore, you are forbidden to me. She said this because she was upset with her for making her pregnant and therefore having to go through the labor pains.}
He said to her: You {our gemara: your mother} are not believed to forbid yourself upon me.

The Sages said to Rav Chisda: But there are witnesses abroad that know that at that time, it was worth a perutah! However, now they are not before us.
He said: Is this not that of Rabbi Chanina? For Rabbi Chanina said: {Based on a rumor that} her witnesses are to the north, shall we forbid {her to a kohen}?
Abaye and Rava do not hold by this of Rav Chisda. They say: If they were lenient by a woman who was captured, would they be lenient by a married woman?

Remnants of that family remained in Sura, and the Sages kept away from them {and did not intermarry with them}.