Question about apostrophe usage with possesive pronouns

In written English, possessive nouns are indicated by an apostrophe.  I am not sure what you mean by possessive pronouns because the grammar books often get muddled here.  These are what I consider possessive pronouns:  mine, yours, his/hers/its, ours, theirs.  No apostrophes are used.

These I consider possessive adjectives but, confusingly, you will often find them termed as possessive pronouns:  my, your, his/her/its, our, their. 

In any event, no apostrophes are used with either possessive adjectives or possessive pronouns.

"the answer is that you can't. Can you think of an example where you might?"

The only time you would write an apostrophe with a possessive pronoun would be to indicate the contraction 's for is:

That's not my jacket.  Mine's over there.

JJM