These medals would have been worn pinned to vest (I found them in an old handbag). Worn to protect the wearer and as physical reminders of their faith.
Pilgrims collected medals from shrines they visited, these are probably from Lourdes.
The wearing of religious medals is a very ancient tradition. The Roman writer Pliny used the word “amuletum” for medals worn around the neck by all classes of people as talismans (objects believed to give supernatural powers or protection to the wearer). Rather than simply eradicating a cultural practice, the Christians instead adopted their use, rooting it in Christian belief and removing the magical connection. (Catholic Education)