PD on a hoop typically represents palladium. Your ring could be palladium-plated if it's PD published around it. HK is really a trademark that stands for Harriet Kelsall. They layout and provide jewellery all over the UK and to other spots likewise. Can “JP” also stand for a distinct nation? https://edgarxuojz.blogsmine.com/37430886/jp88-an-overview