If you found it in a multicomponent site, probably tough to pin down as to time period. If one culture level showed a preference for that particular lithic, you might make an educated inference from that fact, but still there would be uncertainty. I do believe the more a person knows well a site they hunt, the better prepared they are to interpret what they find at that site. At least better then someone who has zero familiarity with that site. Educated guesses are best made by whomever is most familiar with the site, but unless that artifact is actually diagnostic of a specific culture level, I don't know how you can narrow down a date....
