In the College of Frs. Piarists, we can see several shields of Cardinal Rodrigo de Castro. Some of them are different, due to the number of tassels in the final line of the net that appear in it.
This is due to two reasons
1st When they carve a shield the cardinal was not yet one and then three or four tassels may appear.
2º That the stonemason has not found enough space to carve the five tassels in the stone and carves so that one or two are hidden behind the shield, as is the case with the shields that are seen in our building
The number of tassels identifies the ecclesiastical dignity of the shield in question, giving us notice whether it is a priest, a bishop or a cardinal…. Check the following link and you will have enough information to understand the shields of our school.