Okay, I hope you love web research as much as I do.
There's a super site devoted to Asian ceramics-
www.gotheborg.comA HUGE site - find Japanese ceramics on the home page, and open. Look for a link to Morimura and/or Noritake. Morimura was the predecessor of this wonderful porcelain, and that was his name. He has an interesting history, a Japanese man, dealing out of New York City to import the very best his country had to offer. Americans were hungry for beautiful imported porcelains - he got a great idea = why not make the porcelain, and import his own stuff instead of others - thus, was born what we know as Noritake - (historians, mea culpa, I simplify)
Anyway, that is what I think you have - and says Japan ? After 1891, and before 1921. Technically, after 1921 it was supposed to say "made in" Japan. But the world of porcelain is not always exact. The latest would be just before WWII.
Best wishes, hope it's not information overload :unsure: KB