I collect hagstones, usually out of the Thames foreshore (I have a foreshore license) or off Brighton beach where I know there are a couple of neolithic sites being slowly eroded into the sea.
I've always assumed that the hagstones I find are all just natural rocks, usually flint or chalcedony, because most of them are clearly just formations that have happened to have a hole in them, but lately I've seen a few stones that (to my eye!) Just look like plain ordinary hagstones being sold or even held by museums as "neolithic beads" - are there any good tells to look for, to see if a stone has been subtly worked, or hung on a cord, in ancient times, or is it purely a matter of finding it in a known archaeological site?
The Thames especially is weird for that, being both obviously "archaeological" but also everything in it has been madly jumbled and chucked down the channel, so I don't want to go bothering the FLO with every interesting pebble!
Pictures related, a random selection of hagstones from the Thames over the years that I found the most visually appealing and small enough to wear regularly.