No. The liquification of the blood can be accomplished a couple of different ways besides miraculous occurrence.
I don't necessarily believe or disbelieve the liquifaction.
But the liquification has led this community in Naples to tie it to good luck.
That's superstition, which is, I'm afraid, what this whole liquification is, since the Vatican, in 600 years, has not verified the validity of this as a miracle.
There are many miracles which aren't officially approved by the church but are nonetheless worthy of belief. For example, the apparitions at Medjugorie aren't official, yet the faithful are encouraged to make a pilgimage to receive grace. There is a book by Joan Carroll Cruz entitles Relics and it has a chapter about the liquification phenonmenon. The book contains the Nihil Obstat and Imprimitur, which are official declarations that the contents are free from doctrinal error and the faithful can choose to believe or not.