grammaticality - Apostrophe for words ending with the letter S

I always had this difficulty understanding how to depict possessive nature for words ending with s.

For example: Is it correct to say, "James's heart is made of gold"? Or is there any other way to use apostrophes with words ending with S?

Answer

This is up to the writer's style, there are two options:

1) James's heart is made of gold.
2) James' heart is made of gold.

@jsegal the link you posted actually confirms this:

NOTE: Although names ending in s or an
s sound are not required to have the
second s added in possessive form, it
is preferred.