People like to collect Bottles by the name on it, or type of beverage it is or by the town name or state name on it ect, ect.. If you were to just specialize in collecting no name slicks you would probably aquire hundreds of thousands, that would have very little value & take up to much space. And because it's a slick it can sometimes be hard to determine what or where it's from? Not much interest in Slicks. LEON.
Usually not. Don’t hoard them too much unless they are unique. Though I can understand if your newer to the hobby or in area with not really good or not a great amount of bottles. It can be a habit to collect them. Remember: if they are from the 1880s to circa 1915 you can turn them purple. In some cases bottles as late as 1919 and possibly 1920 could turn purple though it’s not exactly very common. A good way to know if they contain manganese is to shine a black light (UV light) on them and see if they have a green tint to them. This will mean the glass contains manganese. There are different ways you can achieve this but quite frankly putting them on a mirror or on black surface in a place that receives a plentiful amount of sunlight, is the fastest way to do it. Usually by just putting them out in the sun, they will turn a nice purple in 4 or 5 years. I’m not sure what time it would take with my methods but I’m sure it would be dramatically faster. It also depends on how much manganese was actually put in the glass itself.