a treasure trove

Translations
кладезь
The library is a treasure trove of information.
Библиотека — это кладезь информации.
Definitions
A treasure trove refers to a collection of valuable items, often hidden or buried, that is discovered unexpectedly. It can also metaphorically describe a source of great wealth or abundance in a particular area.
Words
a

article or possessive pronoun
некий
treasure

noun
сокровище
trove

noun
сокровищница