I have a lot of necklaces that I love, but hail from days past when a shorter length was in style. Instead of spending the money to buy new ones, I have found two simple ways to convert the ones I love to longer, more wear-able options.
First, use the chain from another necklace to add length.
For example, I have this necklace that I am quite fond of. However, with the styles of tops I am currently wearing, it would look better longer. Therefore I found a chain of a matching color and weight and simply clasped one to the other, on both ends.
Voila! Versatile new necklace!
Although I used a chain that would have made the necklace too long, looping the chain around one more time gave me the desired length. The weight of the turquoise necklace made for an awkward choker, but it stayed at a more comfortable and attractive length when a small safety-pin was applied to the back of both loops to hold it in place.
Another option is this, adding ribbon to a necklace to add length.