Sometimes dates can have white spots on the outside of them. This is from the natural sugars crystalizing and making its way to the exterior of the date. Dates have the lowest moisture content (about 30%) than any other fruit, so they are naturally dehydrated. This increases their shelf life. Dates have a long shelf life if stored properly. So, it's best to keep them stored in the refrigerator, where they can last for months, unless you plan to use them all quickly.