Kiddushin, Chapter Two, Mishnah 10. The Mishnah deals with a man who betroths a woman with items that carry sanctity and with the gifts given to the kohanim, and it teaches that although such items are not fit for him in and of themselves, they do have monetary value and they can belong to him.
"HaMekadesh biTerumos uv'Maasros uv'Matanos uv'Mei Chatas uv'Efer Chatas - harei zo mekudeshes, va'afilu Yisrael" - one who betroths a woman with Terumah, with tithes, with the priestly gifts, with the waters of purification or with the ashes of the red heifer, she is betrothed, and this is so even if he is an ordinary Yisrael.
These are the items the Mishnah is discussing:
Terumos and Maasros - the portions separated from the produce.
Matanos - the priestly gifts from a slaughtered animal: the foreleg, the cheeks and the maw, which must be given to a kohen.
Mei Chatas - the water used for sprinkling, to purify a person who contracted tumah from a corpse.
Efer Chatas - the ashes themselves, before they are placed into the water.
With each one of these items the woman is betrothed, since they have monetary value and they can belong to the husband - even if he is a Yisrael and not a kohen with regard to the Terumah and the priestly gifts, and even if he is not a Levi with regard to the tithes.
Mei Chatas and Efer Chatas:
The Gemara points out that the discussion concerns the payment he receives for drawing the water or for the transport - bringing the ashes from place to place and conveying them - which involve effort, and therefore he is entitled to take payment for them. It does not refer to the act of sprinkling upon the person who is tamei, or to placing the ashes into the water; for these one may not take payment at all, since they are purely acts of mitzvah and have no monetary value. But for travel expenses and the like he may take payment, and in that respect he has ownership and the matter is considered to have monetary value.
Terumos and Maasros - "tovas hanaah":
On this point the Gemara brings two opinions. According to the first opinion, the case is an ordinary Yisrael who separates Terumah and tithes from his own produce. Although he cannot keep them for himself and is obligated to give them away - the Terumah to a kohen and the tithe to a Levi - he does have "tovas hanaah" in them: the choice of which kohen and which Levi to give them to. This ability, to give to whomever he chooses, contains a certain measure of benefit that a person has in selecting the recipient of the gift.
From here the question revolves: is that benefit considered to have monetary value? It certainly has some value, but the question is whether it can be called money, actual currency that he holds in his ownership:
The first opinion: tovas hanaah is considered money, and therefore he can betroth her with it.
The second opinion: it has no true monetary value in the sense that one can betroth with it.
The Yisrael who inherited Terumah and tithes:
Therefore the Mishnah is established as speaking of a Yisrael who inherited Terumah and tithes from his grandfather, his mother's father, who was a kohen. He himself is not a kohen, but he inherited Terumah and tithes. And there is no difference whether he inherited Terumah and tithes already separated, or whether he inherited tevel from which Terumah and tithes had not yet been separated, since gifts that have not been separated are viewed as though they had been separated - we look at the priestly gifts that have not yet been set aside as if they already were. For this reason he is permitted to keep the Terumah and the tithe that he separates from the tevel he inherited from his grandfather, and so he has monetary value in them, and with them he can betroth a woman.
In summary: the Mishnah teaches that one who betroths with Terumah, with tithes, with the priestly gifts, with the waters of purification or with the ashes of the red heifer - the woman is betrothed, even if he is an ordinary Yisrael. Regarding the waters of purification and the ashes, the reference is to the wages for the effort of drawing and transporting, and not to payment for the sprinkling, which is an act of mitzvah. Regarding Terumah and tithes, the opinions differ as to whether "tovas hanaah" is considered money, and according to the opinion that denies this, the case is a Yisrael who inherited Terumah and tithes, or tevel, from his mother's father who was a kohen, in which case he has full monetary value in them.