Yes, it is possible for a locksmith to make a key without the original – one of three methods can be used for this.
The first is to cut the key to code. Every lock and key have specific alphanumeric codes that can be used to create copies. If the code is not available, a locksmith can either impression or disassemble the lock to create a copy.
To impression a lock and key, specific tools and experience is required. However, this is one of the most convenient ways to copy a key because it uses the existing lock.
Disassembling a lock is far more complicated and takes the most time. Basically, it involves reverse-engineering the internal components of the lock to create a new key.