This has been covered several times, if you search you'll be able to find all the answers. I'm an agent. Collectibles to us here isn't a collectible to an insurance adjuster. A penny from 1890 is worth $.01. You need to have something separate for anything collectible of value. With my company you are covered but not nearly for what you need to be covered at. It's a set replacement value of $500 because its considered commercial equipment. Other companies will classify it as electronics, which some will have set limits there. Others won't care. It will also vary state to state. The best thing you can do is have a separate policy for them. It was determined here on Pinside that there is a company that sells insurance on collectibles and that was the best route.
And I'm going to say this again and I cannot stress this enough. When something happens, its not your Agent who deems something a covered loss, it is your adjuster/claims department. Check with them at your company.