What to do with the Coin and Neclace Misc items?

Whats its actual purpose? I cant seem to sell the necklace to the jewler and I'm not sure what the Coin item is useful for.

You can sell miscellaneous items in some expansions of Zarista Games. At least there is such a shop in 'Escape from Asteroids', as far as I can remember...
Place them on a shelf with persistent storage until you get there, for example in your house in Mithria.