Glass Packaging Institute the glass finish number. For example, an 8-425 finish is approximately 8 mm neck outside diameter with a 425 finish corresponding to a threaded neck typically found on small vials. Glass Packaging Institute The Glass Packaging Institute (GPI) is the North American trade association for the glass container industry, headquartered in Arlington, Virginia. Through GPI, glass container manufacturers advocate job preservation and industry standards, and promote sound energy, environmental, and recycling policies. The GPI membership consists of 5 glass container manufacturing member companies, and 33 supplier member companies, who provide raw materials, recycled glass, equipment, decorating, and other services to
Glass recycling collection points have separate bins for clear, green and amber. Glass reprocessors that intend to make glass containers require separation by color, because glass tends to retain its color after recycling. If the recycled glass is intended for other products, or if the glass reprocessor uses newer optical sorting equipment, separation by color at the collection point may not be required. Heat-resistant glass like Pyrex or borosilicate glass should not be disposed of in the glass container because even a small piece of such material will alter the viscosity of the fluid in the furnace at remelt. When glass is