With black Silestone countertops, when you touch it or set a pan or plate on it, it leaves a mark that you can still see even after wiping. What can prevent this?
This is a common problem with dark and especially black honed granite, which is easily solved by applying a Color-Enhancing Marble & Granite Sealer that makes the stone darker so the finger prints are not so noticeable.
Of course, you cannot apply a sealer to Silestone, so it’s just a matter of cleaning it. If the finger print oils are staining as I think you suggest (“leaves a mark that you can still see even after wiping”) then that could be a problem you’ll need to contact Silestone or your fabricator about.
Although, you may not be using the best cleaner, which may solve the issue.