i must admit i haven't heard of an oak tree from conkers but horse chestnut trees comes to mind however some years ago when we had dogs we where walking our dogs down a farm track that had oak trees growing beside it
my wife picked up some acorns i said from acorns mighty oaks do grow
and low and behold so they did we potted them on and potted them on and when they got to big for the pots we gave them away and just kept 1 that's quite big now the rest are growing quite nicely in a farmers hedge