I found this article about a time capsule found in a Catholic Church in Singapore quite interesting: 173-year-old time capsule unearthed at Singapore's oldest Catholic church
A 173-year-old time capsule and granite foundation stone of the country's oldest Catholic church have been unearthed, in what experts describe as a "rare discovery".
Contractors found the hitherto missing capsule and foundation stone earlier this year while restoring the Cathedral of the Good Shepherd along Queen Street.
The time capsule - possibly the oldest one found here - comprises publications such as a prayer booklet and newspapers from 1843, as well as 24 international 18th- and 19th-century coins and tokens. A foundation stone, or cornerstone, is the first stone set in the construction of a masonry foundation.
Does the Catholic Church have any regulations (rules, laws or norms) on placing a time capsule in the foundation of a church or cathedral? What may placed in such a time capsule?
As a bonus question: What is the oldest known recorded evidence of a time capsule ever been employed in the Catholic architecture of a church or cathedral?