The Cathedral in Valencia says it has the Holy Grail. Visited my daughter and went to see it. Unfortunately, at the time I was having sight problems, and didn’t get a real good look.
There is a very good description of it in Anne Catherine Emmerich’s “The Life of Jesus Christ”, vol 1. It pretty much matches what they have at Valencia, except that the simple brown stone cup and cover was converted to a chalice by making the cover the base and adding a silver/gold stem.