By the time you are asking this question it is probably too late.
There is a county in Florida where the locksmiths have an 18 month backlog of drill orders from Superior Court on safety deposit boxes in order to gain access to the will people died leaving there. Not only has no one been able to find the will, probably in the box, they can’t find the key to get in any case.
In my county here in Washington State I saw a lawyer ordered to stand watch and inventory the contents of the safety deposit box under these circumstances. What should have been a brief inexpensive court appearance to start the probate became a several thousand dollar event.
Wont a copy do? No.
You know, I have seen a lot of things in my career but I have never known there to be a black market in unprobated wills. It is not likely there will be a theft of this document, so perhaps leaving somewhere people might find it is best. Some say wrap it in plastic to keep it from being ruined and leave it in the freezer. Me, I spent thirty bucks at the hardware store and bought a fireproof box. The key is right there to access, but if it should melt in the fire that kills me I have left the other key with a relative.
Leave the jewels in the safety deposit box. Once the original will is admitted to probate the court will issue your personal representative the authority he or she needs to get into the box, without a locksmith this time.