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How Millefiori Works


Making Millefiori Patterns
Glass artists can mix in different colors during the heating process by dipping their work in a mixture of crushed glass called frit.
Glass artists can mix in different colors during the heating process by dipping their work in a mixture of crushed glass called frit.
iStockphoto/Thinkstock

The cross-section designs of these tiny, usually multi-colored rounds of glass are infinite. Here are a few of the most common.

The artist takes cooled glass canes -- still around 1,000 degrees Fahrenheit (537.8 Celsius) -- and gathers them together around a core in a pattern. When looked at from its end, the grouped cylinders form a picture such as a flower. The artist then reheats the piece in the glory hole.

Artists typically need many millefiori pieces. To create them, two glassmakers attach two pontils -- one at each end -- to the hot glass bundle, and then walk away from each other, stretching the glass. This is almost always a two-person job, although some very long pieces can be hung from pipe holders -- devices used to secure pontils -- and then pulled vertically. The longer the glass is stretched, the smaller the cross-section design gets.

The artist will then use a murrini chopper to slice skinny disks from the resulting pencil- thin cylinder. Murrini is a type of glass art in which multicolored cane is made into thin pieces. The counterweighted wheels of the chopper keep the artist from breaking the rod of glass. At the center of the tiny rounds is the image of the original design. The artist can use the disks alone or group them together using nichrome wire -- a metal wire that can withstand high heat. The bundle is reheated, turned on a marver, stretched and sliced. These slices have even more complex colors and designs in cross-section. The artist can repeat this process as much as he or she likes.

As another option, the artist can dip a cooled cane of glass back into the clear molten glass in the melting furnace. The artist immediately rolls the dipped rod in colored, crushed glass called frit. The clear glass is so hot, the frit sticks to the surface of the clear glass, coloring it. The artist dips the piece back into the clear glass and rolls it once again in a frit of a different color. When the artist is satisfied, he or she reheats, stretches and cuts the layered cane.

Another way to make the pattern is with a die-cut metal mold. The mold can be in any shape or design and can be several inches in diameter. Some are shaped like animal silhouettes, faces, stars or one of many other possibilities. To use this technique, the artist takes molten glass on the end of a pontil and lowers it into the mold. When the artist lifts the pontil out, the glass has taken the shape of the mold. That glass is rolled in another color of molten glass. The artist can do this repeatedly. Finally, the cane is stretched and cut, and the resulting millefiori has the image of the mold in miniature, on its face.