The story
- Proto-West Germanic · inherited from*saltastain
- Old English · inherited fromsealtstān“rock salt, niter”
- Middle English · inherited fromsaltstone
- English todaysaltstone
From Middle English saltstone, salteston, salt stan, from Old English sealtstān (“rock salt, niter”), from Proto-West Germanic *saltastain, equivalent to salt + stone.
Etymology from Wiktionary, CC BY-SA 4.0.