Final answer:
Without a direct reference to a specific work of fiction involving Santiago and the three gold coins, an accurate answer cannot be provided based on the provided excerpts.
Step-by-step explanation:
The question about Santiago and the three gold coins seems to be derived from a work of fiction, potentially a novel or short story, which is not directly referenced in the provided information. None of the provided texts explicitly state what Santiago does with the three gold coins. Therefore, without more context or reference to the specific narrative involving Santiago, a factually accurate account of what he does with the gold coins cannot be determined from the available excerpts.