Ruby Opalescent - A recent addition to our palette of glass colors, this new hue is REALLY RED! Special ingredients in the glass batch are needed to make opalescent glass. During the production process, the molten glass must be briefly chilled and then reheated in order to create the opalescent effect. These two lamps are triumphs of the glassmaker's art.At Fenton, we continue make our glass the ''old fashioned'' way, by hand, using tools and techniques that are essentially unchanged from those of a century ago.