Blue Glass Choker Bezel set pendant necklace on metal band

I constructed this necklace by purchasing the pendant separately from the choker necklace band. The pendant was made by an artisan at a market in Toronto and I purchased a variety of them in different styles at the time. The artisan created the bezel set band to which the loop is fastened. I purchased the metal choker band and put them together. This choker has a modern look. The pendant could be agate or glass, but I am not 100% sure since it has been so long since I purchased it. To me it looks closer to glass based on how the back texture of the pendant looks. The band is silver toned (not silver).