These are a couple of soda pop bottles I purchased at an antique store several years ago. They were manufactured in England between 1873 and 1912 from a 3 part mold. The bottles were filled with a carbonated drink upside down. A gasket at the neck of the bottle and the marble formed a seal as a result of gas pressure in the drink. To open the drink, the marble was hit to break the seal which produced a 'popping sound'. Thus the term 'soda pop'. (I was experimenting with a little light today.)
I really like the simplicity of the shot. I can appreciate how hard it is to capture this in low light. I like the stark black background. Good to know where pop originated!