Dichroic Glass

For those of you who would like to know more information about the brillant propeties of our fused glass pendants and bowls, here is dome information about dichroic glass.

The history of dichroic glass goes back to the 1950’s and 1960’s when NASA, defense contractors and the Department of Defense developed this high-tech material for use as optical filters, as a shield against cosmic radiation and many other uses. For example, the golden sheen on an astronaut’s face shield is a dichroic coating meant to protect against the harsh glare of natural and obviously unfiltered sunlight.

Dichroic glass does not use paints, dyes, gels or any standard coloring agents to create color anymore than a prism does. The fantastic colors are created through the manipulation of light. The multi-colored effect is the result of complex light interactions called “thin film physics”. Thin-film physics are also responsible for rainbow patterns in a soap bubble, the swirling colors in oil floating in a puddle and the dramatic reflections in dragonfly wings.

The manufacture of dichroic glass requires complex processing techniques which has been mastered by only a handful of manufacturers. The limited supply is partially due to the requirement for very high-tech equipment. Dichroic glass is created by carefully heating various metallic oxides in a vacuum chamber to very high temperatures, using a high-voltage electron beam, until they are vaporized and deposited onto the surface of the glass. Time and temperature are used to control the thickness of the oxide on the glass. The complete process may require from 15 to 50 distinct layers of alternating metallic and silicon oxides. The total thickness of the oxide layers may total no more than 70 nanometers (700 angstroms). To put things in perspective, a human hair is 70 microns, or 1000 times thicker than the total oxide layer in dichroic glass. For further perspective, the wavelength of visible light ranges from 400 nanometers (the color violet), to 700 nanometers (the color red). The dichroic coating creates an optical filter that transmits (passes) certain wavelengths of light and reflects (blocks) others. The metallic oxides have no intrinsic color themselves, instead it is the physical properties of the metallic oxides in the dichroic glass that cause different wavelengths of light to either reflect or transmit some wavelengths more than others. These properties cause some kinds of light to travel through the glass along slightly different paths causing the color shift we observe. Most dichroic glass uses both transmission and reflection of light to achieve the desired effect so that as you rotate a piece of dichroic glass, even slightly, you’ll see a shifting rainbow of colors. The type of oxide, like titanium or magnesium, the number of oxides used, the order and number of layers, and the pattern will determine the final effect. With so many variables, dichroic glass presents an incredibly rich and varied palette of colors and patterns for glass artists to work with.

Then there are the challenges involved in using dichroic glass in our fine art glass jewelry. Once the raw sheet of dichroic glass is fused as part of a piece of art glass, its characteristics will change yet again with the new colors shifting towards the blue end of the spectrum.

Gratitude Stones–New Fused Glass Jewelry

I want to introduce you to John Cox.  He is an American artist living in Tulsa, Oklahoma.  He also works in fused glass and he works closely with form and color contrasts to produce works that are both striking and unique.  We will be carring his Gratitude Stones.  According to John, “Gratitude stones act as a reminder to be grateful for all the great things in your life. According to the law of attraction, what you desire also desires you. Look to the universe for what you want but don’t forget to be grateful for what you have now. Wear this stone often as a reminder. It is your birth right to have all the abundance this world has to offer.”  I have included images of two of his pieces: