{"product_id":"vintage-black-opaque-glass-marble-lot-25ct-ribbon-swirl-uv-cadmium-slag-mb15","title":"Vintage Black Opaque Glass Marble Lot 25ct Ribbon Swirl UV Cadmium Slag #MB15","description":"\u003cp\u003eA distinctive 25-count collection of vintage machine-made glass marbles featuring dense, jet-black opaque glass bases accented with dynamic surface swirls, patches, and slag ribbons. Reflecting the classic output of mid-century American glassmakers, this assembly includes crisp contrast designs in opaque white, sunny yellow, vibrant cobalt blue, jade green, and fiery red-orange layered across deep obsidian-toned spheres. Highlighting specialized batch chemistry from the historic production era, select ribbon elements incorporate mineral-based cadmium formulas that react under ultraviolet longwave illumination to produce a vibrant orange-red glow, while subtle trace compounds yield soft greenish fluorescence against the inert dark glass. This cohesive grouping brings together traditional machine-rolled swirl craftsmanship, stark contrasting color runs, and coveted reactive formulations prized by vintage marble and art glass collectors. # MB15\u003c\/p\u003e","brand":"My Consignment Store","offers":[{"title":"Default Title","offer_id":53828054810987,"sku":"MB15","price":50.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0968\/0669\/9371\/files\/IMG_5583.jpg?v=1788951562","url":"https:\/\/myconsignmentstore.com\/products\/vintage-black-opaque-glass-marble-lot-25ct-ribbon-swirl-uv-cadmium-slag-mb15","provider":"My Consignment Store","version":"1.0","type":"link"}