I found two pieces of this pot, about 20m apart, on a beach in Algarve today. They fit together perfectly! I learned that these pots are called “alcatruz” and are a traditional method for catching octopus. How old could it be? I guess that the letters must identify the owner of the pot

I found two pieces of this pot, about 20m apart, on a beach in Algarve today. They fit together perfectly! I learned that these pots are called “alcatruz” and are a traditional method for catching octopus. How old could it be? I guess that the letters must identify the owner of the pot