Sterling silver onyx pendant with charms marked mex'co' 24" ball chain

This is a gorgeous piece of onyx and sterling with handmade charms and a long 24" sterling ball chain. The back is marked mex'co' and not sure if that's 925 or a signature or what I couldn't find information as much as I searched. I love this piece but ended up never wearing so it's time to find a new home to get worn and loved. Vintage from antique store shop. Hqppy to bundle. I have a onyx ring I'm going to list shortly that would go amazing with this. I also currently have a sterling pear shaped onyx ring listed as well. I use recycled packing material unless otherwise requested by message. I am happy to answer any questions.