Rare and Well-Known Objects
If something is rare to possess and well-known, it is being coordinated around. If it did not acquire both of these properties at once, it was either rare at first or well-known at first. If it was rare at first, then become well-known it was used to coordinate and that proliferated it. If it was well-known at first and then became rare, it serves as a reference point of something no longer easily acquired.