[ULPIANUS libro quadragensimo ad Sabinum. ] §13.7.1.prPignus contrahitur non sola traditione, sed etiam nuda conuentione, etsi non traditum est.
[ULPIANUS, on Sabinus, Book XL] A pledge is contracted not only by delivery, but also by mere agreement, even if it has not been delivered.
§13.7.1.1Si igitur contractum sit pignus nuda conuentione, uideamus, an, si quis aurum ostenderit quasi pignori daturus et aes dederit, obligauerit aurum pignori: et consequens est ut aurum obligetur, non autem aes, quia in hoc non consenserint.
Therefore, if a pledge has been contracted by mere agreement, let us see whether, if someone has shown gold as if about to give it as a pledge but has delivered bronze, he has bound the gold as a pledge: and the consequence is that the gold is bound, but not the bronze, because they did not consent to the latter.
§13.7.1.2Si quis tamen, cum aes pignori daret, adfirmauit hoc aurum esse et ita pignori dederit, uidendum erit, an aes pignori obligauerit et numquid, quia in corpus consensum est, pignori esse uideatur: quod magis est.
However, if someone, when giving bronze as a pledge, asserted that this was gold and so gave it as a pledge, it must be considered whether he has bound the bronze as a pledge and whether, because consent was given to the physical object itself, it should be regarded as a pledge: which is the better view.
tenebitur tamen pigneraticia contraria actione qui dedit, praeter stellionatum quem fecit.
Nevertheless, the one who gave it will be liable under the contrary action of pledge, in addition to the fraud which he has committed.