Question

Why was gold so important to people in the gold rush

Answer 1

Because it was a rare element, visually pleasing (used in jewellery), and could be sold for lots of money. It is also very unreactive so it can be used for many purposes (eg. in computers)

Answer 2

If you are asking for grammar help you need to reword your sentence and put a question mark at the end so that it looks like this."Why was gold so important to people during the gold rush?"