I found this piece of DICHROIC GLASS and.......

So, I was wandering through my favorite glass supply store (Romaine's Stained Glass) and saw this piece of glass. I have seen it many, many times before, but this particular time it grabbed my attention because of how the sunlight was shining on it and creating fabulously fantastic colors. As I walked around it, the glass changed colors from gold to purple to purplish red!!! This piece of dichroic glass had to be mine.


And me being me, I had to know what exactly dichroic glass is and why it shows such dramatic and varied colors. I talked to other glass artists,  and researched it online as well. What I found out was absolutely fascinating.
But then....I'm a glass freak. So......here's the Reader's Digest version of what I discovered.


First of all, dichroic glass is not easily obtained. The process to make it is so complex that only a few companies in the world manufacture this spectacular and multi-purpose glass. Webster says the word "dichroic" comes from two Greek words: "di" which means two and "chros" which means colors, or more exactly, skin. This two-colored "skinned" glass is created by a complicated, high tech process in which metals like gold, silver or aluminum, or oxides like titanium, zirconium or magnesium, are vaporized into dust inside a vacuum chamber by the blast of an electron beam. Gravity causes the vaporized metal or oxide dust to gently settle onto the surface of a sheet of hot glass at the bottom of the airless vacuum chamber. This vaporizing and settling of metal or oxide dust onto the hot glass is repeated until there is a "skin" of color on the glass. This dichroic skin looks much like the swirling iridescent rainbow of colors you see when oil floats on water. Once the dust layer is thick enough to see (but still thinner than an onion skin), the coated glass is kiln fired at a high temperature to fuse the metal or oxide to the glass.

I was surprised to find out that archeologists have discovered shards of dichroic glass that date as far back as the 4th century AD when Constantine the Great was emperor of the Roman Empire! Look at this picture of the "Lycurgus Cup" from this time period. The glass in this cup looks green in the daylight and red when lit up at night! Wow! How did the ancient Romans make the dichroic glass that could do this?

Lycurgus Cup (Photo courtesy of Google Images, pintrest.com and rsc.org)                            

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      I was also surprised to discover that the process we use today to make our modern dichroic glass (using electron beams, vacuum chamber, etc.) was invented by NASA beginning in the 1960s to make dichroic glass for use in their satellite mirrors, space suit helmets, and re-entry tiles on the space shuttles! Who knew? This micro-thin layer of metal dust fused onto the glass makes the glass able filter out the light rays that are harmful to astronauts and their equipment when they are traveling and exploring in  deep space.

 Dichroic glass earrings

Dichroic glass necklace pendant

Glass artists used dichroic glass in many ways. One popular use to to make jewelry.

   

Dichroic glass necklace pendant
(Photo courtesy of
en.wikipedia.org)

Other glass artists may sparingly use dichroic glass in their glass art endeavors by cutting and incorporating it into windows or mosaics, but most dichroic glass use for artists is in hot work with fusing, slumping and glassblowing. But you're not an artist, you say?  For my many movie fanatic friends....every time you use an LCD projector or watch a 3D movie you are using a dichroic glass optical filter!!


Needless to say, this glass is rather expensive. You know, the more rare something is and the more difficult it is to make, the pricier it is. I am pondering and dreaming of what this piece of glass will become. Once I decide, I will share it with you and take you on a blog journey of the creation of some spectacular (hopefully!!) piece of glass art from this flat round piece of dichroic glass. I know it won't be anything for space travel and it won't be a piece of jewelry. I do have one or two things in mind though.

References

https://spinoff.nasa.gov/Spinoff2012/cg_2.html 

https://www.theglasscastle.com.au/what-dichroic-glass

http://www.estarlight.net/dichroic-glass.html

https://en.wikipedia.org/wiki/Dichroic_glass 

All photos are my own unless otherwise noted.