Most assortments seem to be assembled by the fabric designer, with all fabrics of a single collection present in the assortment. Collections have names like 'Civil War Homefront', 'Old Primrose Inn' and 'Lakeside Resort'.
However, it seems to be completely impossible to see the fabrics that are in a collection. For our quilt, we decided on the Butterscotch collection, in Bali Pop format. And while the page contains a photo of what's in there, you can't get a detailed view beyond a general idea of the colors involved.
But there are pages with detailed photos of the fabrics themselves. There is just no way to cross-reference them.
I'm new to the whole patchwork/quilt thing, but surely I am not the only one who thinks that is breathtakingly stupid?