If it’s an upper circumstance “L” along with a reduce case “c”, it’s for Louis C Marks who designed jewellery from the 40s. Having said that, this interpretation is more unlikely, as “JP” by itself doesn’t commonly signify a certain metallic standard. Manner-manufacturing.com can be a participant from the Amazon Services https://andreortvy.verybigblog.com/36010048/helping-the-others-realize-the-advantages-of-jp88