From a thread on Dragonsfoot i got to thinking how our books get around.
I know i have books that have been purchased in Nebraska, used in Colorado and Korea. Then returned to Nebraska sold and 20 years later reaquired.
Kinda like the money with the where is George stamped on them. All of my 1e stuff is used. Though some of it is stuff i used and sold and rebought years later.
I think all of this can carry over to treasure.
That sword you got off the orc? he stole it from a farmer in a town raid. The farmers grandfather earned it in a war 50 years ago. The army had gained it as booty from an earlier conquest and it had been forged as a gift to a noble from a greatful king.
Suddenly that old plus one sword has a back story. Give it a name and possibly a minor ability....
True Guard , sword +1 (+2 when deffending your home or leiges lands. Gains 1d4 Bane damage vs invaders)
One minute of thinking to make a unique sword that a player would treasure. Also it can create future plots and stories as people recognise it and covet it.