If you have some glass jar without a joint around the edge, your herb will be exposed to oxydation.
If you stock it in a fridge (well packed in some material that can further isolate it from the too cold temperature of the fridge, like foam) humidity could even gets in it.
So, take a plastic bag, cut the handle, and make your own temporary seal (jars with integrated plastic seal are far better for home storage, and vacuumed plastic pouch/bags if you have to send it over the post)
