Dichroic Glass & Lamp Work Beads
Stars in Ice. Dichroic Glass is like stars twinkling in a piece of jewelry. Dichroic glass, used in the space industry, has come to the world of jewelry. Dichroic, which means two colors, has the ability to show more than one color when viewed from different angles. This glass will show two difference colors when light is transmitted or reflected. Transmitted light is the light passing through the glass and reflected light is reflected off the surface of the glass. This wonderful color change is what gives dichroic glass jewelry its appeal.
Dichroic glass is produced by placing glass in a vacuum and vaporizing metal oxides, such as titanium, silicon, and magnesium. Each oxide or combination of oxides produces specific transmitted and/or reflected colors. This process uses black or clear glass as the base but may use glass that has a textured surface.
When the base glass color is black only the reflected color is visible. When the base glass color is clear both the transmitted and reflected color is visible. Of course, you can change or affect the transmitted and reflected colors by using different transparent glasses. Each combination produces something different. The names of each color combination tell the transmitted and base reflected color. For example cyan/copper, my favorite, will look cyan blue when you look through the glass but will look coppery when viewed at an angle. If the cyan/copper is fused on black only the copper is visible. If it is fused on a medium blue, for example, the cyan is almost not visible as a transmitted color but the copper will look very shiny and yellow. If it is fused on a dark green the copper will take on a coppery hue.
Lamp Work Bead
I may have a love of fire because I became interested in making lamp work beads. Lamp working is a process of making a bead from glass. Using mandrels and glass rods you work with an open flame of propane and oxygen or MAPP and air. There are two types of glass used for bead making, soft glass and hard glass. The terms soft and hard refer to the melting temperatures of the glass. Glass is a mixture of silica and oxides. The proportion of silica to oxides (soda and lime, borax, or lead) will affect the melting temperature. Soft glass, which I use, is a soda lime glass and has a COE (Coefficient Of Expansion) ranging from 89 to 109 depending on the specific formula. It is very important to know the specific COE of the glass used because if two or more glasses with very different COEs are used, they will crack and break.
Glass in its pure state is colorless. To get color metal oxides are added to the clear glass in its molten state. For example silver oxide is used to make yellow, cobalt is used to make blues, and copper is used to make blue-green, green, brown and some reds. Gold is used to make a beautiful deep red glass.
When making a bead, or any glass object, and two or more colors are used you need to be aware that the oxides in the different colors of glass can react with each other. Sometimes two colors can combine producing an third color or sometimes a dark line appears where the two colors meet. A bead maker may take advantage of this and use it as a design element in the bead.
In addition to using more than one color to make a bead, other things can be used to produce patterns on beads. Frit (crushed glass), dichroic glass, enamel powders, mica powders, or metal leaf or foil. Each has its own characteristics and each produces a different effect on the bead. With some items, such as frit or metal leaf or foil, you can produce different effects by varying the temperature at which you work the glass. Or you can combine several items such a putting on a layer of silver leaf and then adding frit.
The combinations are endless. Your skill and imagination can combine to produce an endless variety of beads and glass objects.