From Discworld MUD Wiki
You can pickle an item by the following means:
- zap with a pickling stick (small stick artifact) that can be purchased or obtained by casting Collatrap's Instant Pickling Stick. Uses a bit of magic.items.held.wand.
- pickle with a pickler, found in player shops and in the Magic Emporium off Sator Square in Ankh-Morpork.
- preserve (after you learn the command) with salt.