Matte or brushed silver or gold definitely create a more casual look as do hammered silver or gold elements. All of these look great with jeans. If you want a dressier look with jeans, simply add a pearl strand or a crystal necklace for more pizzazz. Be sure though to wear the right shoes with the dressier jewelry. Some ankle boots or ballerina flats are great as are wedge sandals.
So what makes a necklace dressier? Again, usually it is the chain that it is on. Some chains have much more sparkle and shine than others; if you are going for glam, go for the sparkling chain. Dressier chains also have much smaller links and interestingly enough, the links seem to be round, as opposed to oval. Another element of higher glamour is the faceted briolette stone. When it is in a solitaire setting and very sparkly it creates a highly glamorous look. Can you still wear this type of necklace with jeans? Yes, absolutely, as long as you have the right top with it and the right shoes and handbag.
Source: Trader Lou