You may have seen beautiful jewelry that was labeled 'dichroic' and wondered what exactly that means. Dichroic comes from the Greek meaning two colors. The glass appears to be different colors when viewed from different angles or in different degrees of light. In basic terms, it means that dichroic glass reflects one color when light reflects off the surface and transmits a second color when light passes through it.
Today's dichroic glass is a branch of the space program where it was used in faceplates to filter out unwanted spectra of light. Today, dichroic glass has many different applications, from the beautiful jewelry worn by artists to the optical and security industries. To know more about dichroic glass, you may visit https://www.artglasssupplies.com/coe90-dichromagic-dichroic.
The process used to make dichroic glass is very technical and is called "Thin Film Physics". It is an expensive process in which the glass is first cleaned at the molecular level and then coated with thin films of elements such as titanium, magnesium, zirconium, and others.
The elements are vacuum deposited on the glass. Up to thirty layers can be applied and the elements used are those that give the glass the different colors available. The time required in the vacuum container can be anywhere from two and a half to four hours, hence the high cost of this unique glass.
The glass is sold to artists in small sheets which are then cut by hand to fit the artist's design and melted in an oven for eight or more hours at temperatures that can reach over 1490 degrees. Dichroic glass is also available in glass rods for the lamp art artist to produce beautiful beads. Murano artists use a torch and glass rods to produce the beads on mandrels which are then also put into an oven for about an hour to anneal.