California-based glass artist Loren Stump specializes in an old glass technique called murrine, where rods of glass of different color are melted together to form a pattern which is revealed when sliced. Murrine are designed by layering different colors of molten glass around a core, then heating and stretching it into an elongated structure. When cool, the glass structure is sliced, just like a loaf of bread, into cross-sections of desired thickness with each slice possessing the same pattern in cross-section. The process first appeared in the Middle East more than 4,000 years ago and was revived by Venetian glassmakers on Murano in the early 16th century. Stump has perfected his own technique over the past 35 years to the point where he can now layer entire portraits and paintings in glass before slicing them to see the final results. His most complex piece to date is a detailed interpretation of Leonardo da Vinci’s Virgin of the Rocks, which involved hundreds of glass components that were melted into a final piece. His masterpieces sold for over $5,000 per slice.