by Warren R. Gallé, Jr.

Curiosity may have killed the cat, but it only provides fuel to the fire for a glass collector. Part of the fun of collecting antique art glass is the discovery aspect of it. Logic tells us that only a finite number of pieces were ever produced. Yet, in hundreds of years of collecting, no one collector or researcher has seen it all, and glass mysteries abound. For example, consider the images below:

mtl-1mtl-1a mtl-2mtl-3mtl-3a

Loetz collectors have been aware for some time of a series of pieces resembling the décor Metallin in Victorian-era decoration that seems to predate the normal production series by at least ten years.  Most of these examples are marked in enameled script (occasionhally etched) with the words: “Patent Applied for – Made in Austria” as shown in images mtl-1, mtl-2, and mtl-3. These examples, of course, raise a few questions: What exactly are these early pieces? Was the patent ever granted? What was the patent for? What relation do they have to the décor known as “Metallin”, and why is there an apparent several-year gap in production between the two?

These answers may be found, thanks to a couple of lesser known sources. Let’s begin with the booklet Johann Lötz – Glas aus dem Bòhmerwald 1824-1939 – Waldmuseum Zwiesel/Muzeum Sumavy – Susice a Kasperske Hory, by Jitka Lnenickova, PhD, which accompanied the 1999-2000 exhibition “Johann Loetz 1824-1939 Glass from the Bohemian Forest. In recounting the chronology of events during the rise of the firm under the leadership of Maximilian von Spaun senior (1879-1908), there is reference to the highly successful showing of “marmoriertes” glass (glass made to resemble semi-precious stones) at the Chicago Exhibition in 1893, and then goes on…

“a year later (1894) in Antwerp the company received an honorary diploma for the high quality of the glasses in the colors of semi-precious stones. A catalog mentions, for example, the glasses in the colors of Rauchtopas (smoky topaz), Onyx, and Carneol, decorated with colored stones in montages. However, the following were particularly appreciated: “Hütte-formed” glass, and so-called ‘Metallglas’ (glass with metallic luster).”

Here we have a contemporary mention of glass that looks like metal in 1894, some ten or so years before the factory introduced the décor we know as “Metallin”. Given the shape and decoration of all the examples shown, the 1894 reference certainly fits. For the answer to the patent questions, we may turn to the book Loetz Austria 1900, by Waltraud Neuwirth. Page 303, which reproduces the text for Austrian patent number 24/696:

 1896 Privilege No. 24/696:

Metallic shimmering glass objects and their production process by Max Ritter of Spaun, owner of the company Joh. Lotz Wwe. in Klostermuhle, Bohemia.

The present invention is related to methods used to provide glass objects, in particular their internal surfaces, with a metallic luster.

Until now, for manufacture of such metallic-shimmering objects either metal coating was used or they were treated with silver acid, reduced in the painter's muffle with the aid of gases.

According to the present invention, the inner side of a glass object is formed from a single layer of glass dyed with metal oxide and metalized directly in the glass furnace, so that the object appears completely finished after removal from the cooling oven.

Such glass objects, decorated on the inner side, represented by the accompanying specimen in one of many possible execution forms, differ essentially from the known metalized-looking glassware insofar that they need not be treated in a muffle with reductive gas to obtain metallic luster, but after the blowing and fire-polishing of the object they acquires the luster by itself.

In order to metallize a glass object on its inner surface, the process is carried out in such a way that, primarily from a metal-oxidized glass a small flask is formed. It is rounded like in the traditional process and then coated in another glass mass until the glass quantity required for the blowing out of the object is present.

After blowing out, the bottom of the object is fixated with the so-called staples for the purpose of treating the opening and fire polished. The glass, now exposed with its inner surface, containing metal oxides, is exposed to reductive carbon oxides in the glass furnace, so that a portion of the metal particles is deposited on the surface, thus producing metallic luster.

New and the object of the present privilege is:

  1. 1.The process for production of glass objects metalized on the inside surface, characterized in the way that a glass bulb/flask, containing metal oxides, is coated with another glass mass and blown in the standard manner fixated and fire polished, after which the glass containing metal oxides on the now exposed inner surface is exposed to the action of reductive gases in the glass furnace.
  2. 2.As new industrial products glass objects, which appear to be metallic on the inner surface according to the method described under (1).

Vienna, 28th of April, 1896                       AUTHORIZED REPRESENTATIVE H. Palm (Michalecki & Co.)

The authorized representative mentioned at the end of the patent, H.Palm (Michalecki & Co.) was a patent attorney in Vienna. The patent describes in detail the process for creating glass vessels with an internal metallic sheen. Although initially very well received, the surviving examples seem to indicate that “Metallglas” was only produced in a small series – but why? To understand this, we must look at what was going on at the company during this time. Note the patent date of April 28th, 1896. The previous month, in March of 1896, von Spaun was notified that Loetz was authorized to participate in the upcoming Exposition Universelle in Paris in 1900. It so happens that the following year, (1897), von Spaun was exposed to, and studied, the work of L.C. Tiffany at exhibitions in Reichenberg (Liberec) in the summer of 1897, and later in Vienna). While this was not the only trigger, von Spaun surely saw the possibilities and was granted in that same year a patent for their own process for iridized decoration,and they began to market Phänomen Genre glass in the first half of 1898.

From 1898 through about 1904, production in Klostermühle focused heavily on Phänomen Genre and other iridescent glass. Initially, this was no doubt in preparation for the Paris Exposition, where Loetz received a Grand Prix medal, right alongside Emile Gallé of France, the aforementioned Tiffany of the United States, and their fellow Austrians at J&L Lobmeyr (among others). Silver medals were also awarded to Eduard Prochaska and the designer Franz Hofstötter.

After 1904, the artistic vision at Loetz began to broaden, and an emphasis on brilliantly colored internally decorated pieces began. Titania (a true innovation), Carrageen, and Markasit Genres were introduced, along with Melusin and an updated version of “Metallglas” in vibrant green, blue, brown, and red, utilizing the optic qualities of the glass and under the new décor name “Metallin”. It seems, therefore, that although Metallglas was enthusiastically received when it was first produced, fortuitous events and changes in the market led the company in another direction, and for several years, there was a break in production of this type of glass. But, when internally decorated glass became the fashion, the time would have been right for a re-introduction of metallic glass using updated colors and textures.


The timeline:

  • 1890 Carneol (marmoriertes glass) first exhibited, Agriculture and Forestry Exhibition in Vienna.
  • 1891 Rainbow Glass as a novelty at the Exhibition of the Applied Arts Association in Vienna.
  • 1893 Chicago World’s Fair -other varieties of marmoriertes glass.
  • 1894 World Exhibition in Antwerp – jeweled marmoriertes glass on display, along with so-called “Metallglas” (glasses with metallic luster)
  • 1896 (March) – von Spaun notified that Loetz was authorized to participate in the upcoming Exposition Universelle in Paris in 1900.
  • 1896 April 28, 1896, privilege 24/696 granted to von Spaun for glass with a metallic interior shimmer
  • 1897 von Spaun, having seen the work of Tiffany, and knowing his firm’s own capabilities, gets a patent for a method of producing iridescent glassware. Phänomen Genre glass begins production later that year.
  • 1898-1904 Heavy emphasis on Phänomen type glass.
  • 1900 Paris Exhibition – Loetz wins Grand Prix medal for its Phänomen Genre glass.
  • 1905 New decors featuring internally decorated glass (Metallin, Melusin, Carrageen, Titania, Markasit) and applied decoration.


We can see here that when these events are laid out in a timeline, the gap between the introduction of “Metallglas” and the production of “Metallin” makes sense. After the initial wave of success with Phänomen genre glass, the factory certainly had the freedom to explore new methods, and even re-visit and re-vamp some old ones.



Loetz Advisory Group, for their ongoing advice and encouragement

Andy Jelcic, for his advice and help with translation of German texts

Photo Credits:

Brian Severn, Kai Hasselbach, Loetz.com and Warren Gallé


Johann Lötz – Glas aus dem Bòhmerwald 1824-1939 – Waldmuseum Zwiesel/Muzeum Sumavy – Susice a Kasperske Hory, by Jitka Lnenickova

Loetz Austria 1900 – Waltraud Neuwirth

Loetz Bohemian Glass 1880-1940 (Hatje Cantz publishers)