Upvote:3
It appears that the loan was issued in guilders and along the way was converted to dollars for transport to the US...
“Correspondence of the Late President Adams (Continued).” April 24, 1811. Excerpted from the Boston Patriot.
I then completed a new contract with the three houses, Wilhelm and Jean Willink, Nicholas and Jacob Vanstaphorst, and De La Lande and Fynjee. In the two former houses, the Willinks and Vanstaphorsts, I was not disappointed. De La Lande and Fynjee, in a few years failed [….] The Willinks and Vanstaphorsts continue, for any thing I know, to this day, 1810, bankers of the United States. I found them men of honor, and they borrowed for me, before I left Europe, nine millions of guilders, which enabled me to send, through the house of Le Couteuæ in Paris, by the way of the Havana, very large sums in dollars, to Mr. Robert Morris, the financier of congress; which enabled me not only to maintain myself in Holland, France and England, but to maintain Dr Franklin and Mr Jefferson in France. Not a livre could Dr. Franklin obtain from the French court, not even for his daily bread, after it was known I had money in Holland. […] John Adams Quincy, September 24, 1810
Elsewhere in the correspondence Adams states that the Dutch expected to be repaid as trade with the US would flourish.