Javier and Efrén achieve a fabulous effect with the dynamic design of this set of six rock glasses. Each glass is crafted with traditional blown glass techniques, in which artisans blow through a metal pipe while twirling it with one hand. They simultaneously shape the molten glass at the other end while expertly achieving a whirling effect in cobalt blue and white. Because each piece is handmade, shape and size can vary slightly and tiny bubbles may appear within the glass. This exemplifies the hand-blown technique, making every piece a unique example of blown glass craftsmanship.