Question: I know jewelry is not a way to make money as far as reselling it. With that said what types of jewelry gets the most amount back if it does come to selling it? Gold, silver, diamonds? 

Answer: In my opinion, jewelry made entirely out of gold, 18K or better sell best. And rare diamonds sell well on auction too. The problem is that jewelry is often bought for several times the worth of the gold to begin with, so you start pretty deep in the hole. Bullion coins, like Krugerrands or Pandas, sell much closer to the price of gold, and are appreciated more. 

What color jewelry like gold or silver would look best with a brown halter dress with copper colored sparkles. It’s for my 8th grade prom. I have matching brown shoes. But don’t know what kind or color jewelry to wear.

Answer:
Of the two choices, gold. But I’d prefer a rose gold to yellow gold, if you cant find one of those, you can use copper.