Definition of Non-renewable Resources
An economic resource that cannot be replaced once used. Examples of non-renewable resources include:
Some resources are potentially renewable, but, overconsumption could also permanently deplete them. For example, fish stocks are generally renewable. However, if there is over-fishing then a species could be made extinct in a certain way.
Something like oil and coal take millions of years to form so are for all intents and purposes non-renewable once stocks are used.
Genetic Pool. If species become extinct then we loose their unique genes and chance to use that in medicines.