There are two kinds of sodium lights: Low Pressure (LPS) and High Pressure (HPS). These lamps are mostly used for street lighting as well as industrial uses. The lamp works by creating an electric arc through vaporized sodium metal.
Enhanced Turquoise. Enhanced Turquoise is a natural stone that has only been treated with either chemicals and heat, or just heat to enhance the color and harden the stone. This type of treatment keeps the color from fading over time and makes more of the harder turquoise available for the market.
The contrast between the color of turquoise and the color of matrix {or mother rock} enhances the beauty of each stone. Many mines produce distinctive stones whose origin can be identified by an experienced person. Enhanced turquoise: The Zachery or Foutz process impregnates turquoise with vaporized quartz.