Encalmo (classically known as Incalmo) is a Venetian glass blowing technique that involves fusing different glass sections. Encalmo pieces are traditionally worked with several bands of color, stacked ontop of eachother to create a uniquely heady aesthetic. This is an impressively tricky technique to get down, as colors require different temperatures to work without damage.
“Incalmo” literally means “graft” in Venetian, and that’s the perfect word to describe this technique. In order to make an encalmo piece, glassblowers must work two separate bubbles of glass and then join them together. In order to join the separate parts, glassblowers open the end of each bubble and join them in the flame. The joining is particularly difficult because the lips of both bubbles must be identical sizes to be joined correctly. Traditional encalmo vases and receptacles feature two or three different colored sections joined together. Contemporary functional glass pieces often feature several encalmo sections, creating a one-of-a-kind spectrum of color.
In order to make crazy encalmo pieces, glassblowers prep encalmo sections of whatever colors they’d like to work with. This process is slow and steady, as glassblowers repeatedly stack colors on the flame and then condense down the sections. Once the tube is smooth and even, it’s ready to be worked into a piece!
As if making encalmo prep wasn’t tricky enough, the cooling process is especially stressful for the piece. Different colors of glass are made up of different formulations. These formulations result in the glass shrinking or expanding more, depending on temperature. When placing an encalmo piece in the kiln to cool, one colored section of the tube may want to shrink more than the section directly above it. This difference is great enough to cause cracks where the colors are fused together, resulting in a broken and unsellable piece.
While the technique is tricky to truly get down, encalmo enables blowers to blend colors in a particularly unique manner. It’s a skill that’s only practiced by master glass blowers, as it requires a significant amount of training and discipline.
There are many different ways to make encalmo pieces. A frequently used technique is called coil potting. Coil potting is essentially making a hollow glass structure on the end of a blow tube that can be blown out into a section. If a glassblower wanted to prep an encalmo section using the coil pot technique, they’d grasp their blow tube and the first color in the encalmo and warm both up slightly. The glassblower then works the color stick around the blow tube by steadily coiling the hot color around the tube. It’s important that the glassblower stay on the outside of the tube wall, as coil potting too close can result in the section closing up. Whenever the glassblower wants to add a color to the coil pot, they’ll grasp a new color stick, heat it, and repeat the process, starting where they left off.
Once the glassblower has used all the colors they’d like in the encalmo, they have to even out the walls of the section by puffing it out and condensing it down. It’s important to do this a few times to make sure the thickness is consistent through and through.
An excellent example of encalmo is the Northern Waters Purple Rain Cluster piece. This heady is absolutely stunning, and features encalmo layers of purple rain and rain drop. Check out the piece to see how clean each of the encalmo layers are.
Encalmo is an ancient glass technique that’s been adapted to heady glass art to create crazy spectrums of color. Keep an eye out for encalmo pieces on Smoke Cartel.