There are two ways to store photos in iPhoto. One is fully importing them into iPhoto structure, and the other is leaving them in place and just recreating scaled down versions in iPhoto structure. You select this in iPhoto preferences. If you went with the former choice, copying the iPhotot folder to your Monument drive, and then importing it should work. But since iPhoto keeps multiple sizes, Monument may end of with size duplicates. In the second option, the pictures are held in alternate sizes and not original sizes, and that will result in resolution loss, unless you deliberately import the originals, wherever they are.