Degenhart Owl Glass Types and Finishes
In this section, we will cover the various glass finishes that Degenhart owls came in and the process of how they were made. We will also cover the different types of glass that Degenhart owls were manufactured in, such as opalescent, milk, and slag glass. After reading below, we hope you'll feel more confident identifying the many unique finishes and types of glass in Degenhart Owls.
Degenhart Owl Glass Finishes
Glossy Finish
For Degenhart owls to get a beautiful glossy finish, they have to take a couple of trips through the glazer, a large kiln with flames directed at the glass. The owls are rotated in a circular motion through the glazer. As the owl moves through the glazer, intense flames fire the glass and melt off the very outer layer, leaving it with a smoother, shinier finish. This important part of the process is actually polishing the glass. This is the reason your Degenhart owl has such a glossy surface.
Carnival Finish
During the manufacturing process, if your Degenhart owl was supposed to have an iridized (carnival) finish, it headed over to a separate spraying booth. While the owl was still hot from the glazer, it was sprayed with metallic oxides (sometimes called metallic salts). The metallic salts react to the heat of the glass, which brings out the iridescent properties of the metallic oxides, creating a rainbow iridescence across the surface. Carnival finishes can vary greatly, from traditional rainbow colors to hues of copper, gold, purple, and green. They can have quite a stunning effect.
Satin Finish
Owls that were supposed to have a satin finish were produced by spraying hydrofluoric acid or hydrofluoric acid fumes on the surface. The acid cuts through the uppermost layers of the glass to give it a satin-like look and feel and remove the shine. Certain colors can appear very similar to sea glass. Collectors have become quite fond of satin finishes because of this. The owls in the middle and on the far left are Westmoreland owls. We used them as examples due to a lack of satin versions available in the Degenhart owls.
Different Types of Glass
Opalescent Glass (Opalescence within the Glass)
There are three kinds of glass which are called “Opalescent.” This particular kind is a blue-tinged semi-opaque or clear glass with milky opalescence in its center. The color is produced by the slower cooling of the molten glass in those parts that are thick, causing some crystallization inside the glass. This kind of glass glows a golden color when light shines through it from behind and a beautiful blue when the light shines onto the surface from the front. Opalescent glass can have various colors of slag added in as well. Pictured in the center above are three different examples of Opalescent glass. On the far left and right are images of it reacting to sunlight lighting the glass from the front and behind.
Slag Glass
Slag glass is characterized by an opaque or translucent glass base with marbelized swirls of a different color mixed throughout. Slag glass owls can consist of two up to possibly 7 different colors. The variations can be really apparent or sometimes subtle, depending on how much of a certain color was present when the batch of glass was made. Sometimes slag glass can be different shades of the same color. For example, a lighter brown mixed with a darker brown.
Slag glass owls could be incredibly challenging to create. They would often have compatibility issues when mixing colors; this would cause frequent breakages and losses in the owls during production. It could be very costly because of this. Due to their gorgeous colors and patterns, slag glass Degenhart owls tend to sell the very highest and are very sought after.
Milk Glass
Milk glass is believed to have been made at least as early as the 1500s in Venice, Italy. It was originally introduced as a lower-cost alternative to porcelain, which was highly prized and being imported to Europe from China. Milk glass often appears completely opaque. However, it can also show various degrees of translucency, permitting some light to shine through when held up to a strong light source. Milk glass comes in a variety of shades besides just white. It can also be blue, green, light orange, pink, purple, turquoise, yellow, brown, and even black. To create milk glass, early manufacturers added arsenic to their standard glass recipes, which yielded a faintly grayish but nicely opalescent effect. Later versions of Milk glass were formed from compounds of bone ash, antimony, and tin dioxide. These composite formulas often resulted in a deeper, more purely white hue.
Degenhart owls have quite a few milk glass colors. Pictured above, from left to right, are the following: Misty Green, Pink Lady, Louise Lavender, and Milk Blue.
Warmed in Effect
Degenhart has several different colors with a "Warmed in" effect. In lighter-colored owls such as the Wonder Blue owl (pictured left), it creates an opalescent effect on the surface. For owls with a red base, it can cause a much deeper or darker red to be present. This effect is created by re-heating parts of the molten glass when it has just started to cool. Heat-sensitive chemicals in the glass turn the re-heated sections a translucent white, such as the owl on the left or a deeper red, such as the owl on the right. The easiest way to do this is by putting the newly pressed glass back into the furnace entrance, and those parts closest to the heat will turn white.
Alexandrite Glass (Heatherbloom)
The color Heatherbloom is actually Alexandrite glass. Translucent Alexandrite glass appears lilac (or sometimes pink) in natural sunlight or yellow artificial light. It looks smoky blue in fluorescent or white light. This is due to the presence of Neodymium oxide (Nd²O³) in the glass. Some owls are naturally more purplish, while others look more pink. The more purple owls have a stronger reaction to the fluorescent lighting and turn a brighter blue. Please see the images above for color comparison in different lighting.
