Kamasutra 6.5.7

6.5.7

suvarṇarajatatāmrakāṃsyalohabhāṇḍopaskarāstaraṇa^prāvaraṇavās oviśeṣagandhadravyakaṭukabhāṇḍaghṛtatailadhānya^paśujātīnāṃ pūrvapūrvato viśeṣaḥ/

Now, the Sages are of opinion, that, when a courtezan has the chance of an equal gain from two lovers at the same time, a preference should be given to the one who would give her the kind of thing which she wants. But Vatsyayana says that the preference should be given to the one who gives her gold, because it cannot be taken back like some other things, it can be easily received, and is also the means of procuring anything that may be wished for. Of such things as gold, silver, copper, bell metal, iron, pots, furniture, beds, upper garments, under vestments, fragrant substances, vessels made of gourds, ghee, oil, corn, cattle, and other things of a like nature, the first viz., gold, is superior to all the others.