Aurfil has 270 colors....2311 is "muslin". On the online color chart it does not look silver blue, it is a very light cream. You could see if you can find a place to buy a color card for Aurfil. Then you could see which color would match the closest to what muslin you actually have. Color cards can be pricey but if you like that thread, it is great to have actual samples of all the colors. I have several color cards but none for Aurfil. Another option would be look at the color cards online and pick 3-4 that look closest to the muslin you have. As they all will be natural colors, you probably will use them all in the future for something...yeppers….I have a fairly large thread "stash" to go with my fabric stash. I haven't been to quilt shop for quit a while even before Covid-19 as there is no need and I am trying to use some things up.