Just speculating, but these may be solely for cash loot if they're selling for that much platinum. Ravens and treants obviously aren't going to be dropping gems, and not many items drop off yard trash in PoN.
Caharrin Westland 52 High Elf Magician Erollisi Marr server
Found one of these in Crushbone-someone dropped it and left it on the ground. I ran into Kelethin, sold it to a merchant for 83 platnums! I still have no idea what it is used for.