Hi. Welcome.
If you could hook up with a collector in your area, that would be most educational.
You could empty one jar at a time and give us a group shot and we could maybe give you an idea of whether we're looking at old and/or valuable marbles. Be careful when you do empty the jars. Don't slosh them around a lot or shake them out of the jars. Condition is vital when it comes to value. One nick could reduce a marble's value by half.
(It's best to start a new thread for each group. Also, small groups are preferred, but biggish groups are okay for giving us a general idea of what we're working with.)