I have been trying to remember a movie I saw a long time ago. It's an old movie, and all I can remember is basically thisngirl who was a mermaid, was turned into a human and went with people (doing heck if I can remember) but I remember a point where they were in a temple and she turned back into a mermaid and some guy touched a statue and was turned into gold I believe. The other people had to drag the mermaid out of the temple on a rug and it ended up having jewels all over it.

Magic Island (1995) ?
From Wikipedia: Jack Carlisle is a disillusioned 13-year-old boy. His mother is always away at work since his father left. He decides to run away, as he feels his mom won't miss him. As he is ready to leave, his nanny convinces him to read a 'magic book' that belongs to her. The book is about a pirate adventure on Magic Island. As Jack reads the book, he is sucked into the world and goes on numerous adventures with Prince Morgan, while fleeing the evil Blackbeard the Pirate. He is even saved by Lily, a beautiful mermaid he falls in love with. Lily is given the power to turn into a human and accompanies Jack on his adventure. Along the way, Jack encounters sand sharks, a tree that grows the favorite food of the person who climbs it, and a cursed temple full of treasure. Jack also uses items he brought along with him in his "magic" bag to stop the pirates.


https://en.wikipedia.org/wiki/Magic_Island_(film)