The Royal Collection,
Several were included in a 2008 exhibit at the Queens Gallery,
Rare book collections sometimes hold high-quality reproductions (facsimile reproductions?) of the complete "Insects of Surinam' folio and other work. (Perhaps the Bancroft Libraries, for those locally in the SFBA.)
Thank you, Kathryn, for the link to the Atlantic article.
I saw her work at the Special Collections Library at Washington University in St. Louis ó I think. It would have been over 20 years ago, and they may have been prints. It was part of a bequest someone had given to the library while they were still living. I donít recall the gentlemanís name, but I spent the afternoon with him and he was treasure.That aside, a quick google search brought up the Getty, so you might start there. They staged an exhibition on her work and life. The curator of the exhibition would surely know where her original works are.Searching further, I see that Peter the Great bought all her original works and they reportedly remain in Russia. This is off a web pageÖ so Iíd research it further just to make sure. And I guess that means I must have seen prints 20 some odd years ago. Wikipedia says Peter the Great bought ďa significant numberĒ of her works which are kept in academic collections in St. Petersburg. There are references listed on the Wiki page.Prints have appeared on Christies for as much as $238,000.Pages mention that her engraver was Joseph Mulder, but close attention should be paid to the engraver, as the engraver often was an artist in his own right. Think of Tennielís Alice In Wonderland drawings - very pale pencil drawings that the engraver transformed into the drawings we are familiar with. Marianís paintings were done on vellum with watercolor and/or gouache (apparently women were not allowed to paint in oils due to some artistís guild rule).This page has a lot of good info:That ought to get you started.