If they are still in business, I would contact the Corp. and standing of the certificate. The shares may have already been redeemed without the Certificate being turned in, (i.e.: Probate, Certificate Loss, etc.). Having the paperwork does not ensure ownership.
Unless the certificate is in your name, then no, there is no value. It's the same as if you had possession of the deed to someone else's house. It has to be signed over to you or it's still their house.