How did you miss that during the Rosary we are to meditate on events in the life of Christ. The mysteries that are about Mary are limited. They are Mary’s Assumption into heaven and her being crowned by Jesus. These alone can be said to be extra Biblical and based on Tradition. The other mysteries are all Biblical.
That’s a very good way to explain it. I tried to, but got a little tangled. I meant mysteries pertaining to stages in the Lord’s life, and added the part of the “Stations Of The Cross”. Of course, “The Stations...” are part of the mysteries, but not that alone!