P.R. Laws tit. 10, § 1652
If the loan consists of money, the debtor shall pay it by returning an amount equal to that received, in accordance with the legal value the money may have at the time of return, unless there was an agreement with regard to the kind of money in which the payment was to be made, in which case the fluctuations in value shall be lost or taken advantage of by the lender.
In loans of bonds or securities the debtor shall pay by returning the same number of the same kind and same conditions, or their equivalents if the former have been done away with, unless there is an agreement to the contrary.
If the loans are in kind the debtor must return, unless there is an agreement to the contrary, a similar amount in the same kind, and quality, or its equivalent in cash if the kind due should be done away with.
History —Commerce Code, 1932, § 230.