First of all, it is close to impossible to get an accurate feel for the age of an Agate bead from a photo alone...too many factors to consider, lighting and computer settings can give a false reading image from one screen to another, the photo may not be correct as to the true nature of the bead as well....then we have the wear issue, was a bead interred as soon as it was made or was it worn for generations? Was it gently worn or was it abused? Was it buried in an acidic setting or highly alkaline soil? Lots of factors that can change how a bead appears today...Dr Mark Kenoyer uses perforation impressions to help determine how it is manufactured, leading an assumption as to the date it was made (unfortunately not 100% reliable) most other bead "experts" have to use personal experience and in-person examination to form an opinion....but that's all it is, an opinion.....too hard to give a 100% guaranteed, factual idea on the true date of any of these....we have to trust our instincts and experience when dealing with these......I have found that even the most honest and experienced dealer/seller can fall short of an accurate analysis....just my humble opinion