The white gold and zirconia prop used in the movie cost around $8,000 but if it were real at 56 carats, it would be valued at more than twice what the Hope Diamond is. Leave it up to Hollywood to invent fictional jewelry and then assign a value it.

What does this mean? They had jewelers create a bespoke (non-diamond) necklace, but it had to be good quality because of the close-ups they wanted to do with it. As for "assigning it a value", isn't that just what people are willing to pay? $8,000 for a one-of-a-kind piece of jewelry and cinema history doesn't seem too crazy to me...