Hey there! To be honest, I had to Google to see what a Cuban chain looks like, and from what I see, it’s simply a heavy flat cable chain. So if you need to adjust the length, it should be just a matter of removing a link or two. Check gold cuban link bracelet for details.

It is unlikely that you have a 24 karat gold bracelet. 24 karat gold is too soft for use in a bracelet. It would not last very long.

If you are selling it as piece of jewelry, it is worth whatever you can persuade a buyer to pay. If you are selling to a gold dealer, the dealer will pay you at the current price of gold minus about 20–30%. It is more likely 14 karat or 18 karat (assuming that it is labelled correctly).