The exact shape and proportions vary between techniques and periods. These graphics are for recognition purposes and not suitable for trying to identify fake marks.
De Bazel etsmerk K.P.C. de Bazel (1869-1923)

Graduate of the Academy of The Hague, the architect had worked for Cuypers, before striking out as an independent. De Bazel supplied his first designs for Leerdam in 1917 and continued by developing a range of modular designs for stemware. The basic shape was defined in in 8 basic service patterns named A-H. They could be easily adapted for 'geringd' (external horizontal ribs), 'geslepen' (cut in a range of patterns) and sometimes inverted ('omgekeerd') or made with optical vertical ribs ('optiek').
His pressed flatware service designed in 1920 was extremely popular, was extended several times, and was produced in a range of strong colours. As an early icon of Dutch currents within art-deco, it has become very collected. A pressed glass milkjug in this pattern might well be priced over 500 euro.
This mark was used for his early work 1916-1921.
De Bazel etsmerk K.P.C. de Bazel (1869-1923)

This revised mark was introduced in 1921 and stayed in use until the last of his designs was produced in 1943.
De Lorm etsmerk Cornelius de Lorm (1875-1942)

Influential designer who was self-taught and, following his involvement with the members of 't Binnenhuis, rose to be the main graphic designer for the Dutch Post Office (1906-1930). He also sold his own work from his own gallery 'de Zonnebloem' in The Hague from 1917 until 1929.
His designs for Leerdam are important developments towards further simplification in form, and although he didn't design very many items, they are all distinctive and influential elements in the Leerdam tradition. De Lorm was also a designer whose work was particularly appreciated by the critics and industry observers, and therefore an important member in the developing stable of glass designers which Cochius was keen to establish.
He also designed earthenware for Plateelbakkerij Zuid-Holland (1925-26)
Lanooy etsmerk Cris Lanooy (1881-1948)

Having established his career in ceramics from 1907, Lanooy was already working for potteries of Rozenburg, Gouda and Purmerend, when he was introduced to Leerdam by de Bazel. He produced a large number of drawings and designs of which comparatively few made it into production.
His early work in applying painted decoration to existing designs (1919) was quickly extended to the design of his own glassware forms, inclufing water-carafe, jugs and vases. Responsible for the design of the first 'oranjevaas' (Juliana in 1927), he spent much of his time working on experimental techniques and finishes, some of which were shown in his one-off ('unica') pieces.
Copier etsmerk Andries Dirk Copier (1901-1991)

Having started work at Leerdam as a 13 year old assistant to his father, a glass decorator, Cochius helped him through day-release classes in typography, and he was put in charge of producing the new designs from de Lorm and de Bazel, which led him on to designs for fairs and shop displays as well as increasing interest in (graphic) design.
Following his first glass designs in 1922 he became the company's only full-time designer, and completely dominated the catalogue through a golden age until 1960, producing some of the best known designs in modern Dutch glass.
From 1960 he began to concentrate on producing Unica, travelling to various countries to work with other glass blowers and contributing to numerous projects at home and abroad. (more...)
Berlage etsmerk H.P. Berlage (1856-1934)

One of Holland's most famous architects, Berlage had already had contact with the Leerdam factory around 1900, but ended up giving his designs to French factory Pantin. In 1923 contact was renewed, and Berlage designed flatware which was intended for production in graniver, but never made. In 1924 Leerdam produced a pressed glass service in yellow arcopal which has noted as a significant work by the art-deco bibles. A considerable part of the design work for the project is attributed to Piet Zwart, who worked for Berlage at the time.
The Ovata service with associated whisky decanter and waterjug, came onto the market in 1928 with several extra sizes added the following year.
Lebeau etsmerk J.J.C. Lebeau (1878-1945)

After the rejection of his early approaches to Leerdam, and an unsuccessful proposal to recycle the waste glass from Philips lightbulb factories, Chris Lebeau met Cochius again in 1923 having built a good reputation in fabric design. He designed vases which were blown in moulds and then hand-finished. Many of them were very large, and were offered with black stands, He also produced vases to stand on the floor and even a large fishbowl on a column.
From 1926-1930 Lebeau worked at the Moser factory in Bohemia (Czechoslovakia).
Bloch etsmerk Lucienne Bloch (1905-1999)

After studying at the 'Ecole des Beaux Arts', Cochius, who had met her father, Ernest Bloch through the American architect Frank Lloyd Wright, invited her to Leerdam where she was inspired by the glass sculptures of Stef Uiterwaal.
Her best-known designs include a fawn, a lioness, and several ducks, all of which were produced with a satin-etched finish. She also sculpted the female form as a nude, and seated on bookends, and is known to have produced several car mascots.
Falkenberg etsmerk Ida Falkenberg-Liefrinck (1901-)

Predominently known as an interior-designer, and one of the few women to play an active role in the development of 'het nieuwe bouwen'. She is famous for several of her furniture designs including rotan dining chairs for Metz&Co.
In 1940 Leerdam produced a service of glasses called Ifa, and followed with a selection of playfully formed vases and gourd shape decanter with an ice reservoir.
Falkenberg etsmerk Sybren Valkema (1916-1996)

Brought in by Copier from 1943 as a lecturer in aesthethic design, deputy director of the Rietveld Academy in 1949 and was responsible for building the oven there which led to the Glass Working Group. Designed stemware forms, 'serica', 'unica' for Leerdam and part of the joint collection of industrial vases, 1961.
Valkema was part of the industry experimental ceramics group at the Porceleyne Fles in Delft (1956 -) and a founder of the World Crafts Council (1964) and, after retiring in 1981, travelled the world to visit colleagues, and contribute to numerous projects. Returning to Amsterdam in 1985 where he built his own oven, the workplace for Hannes den Hartog, Leendert van der Linden et. al.
1994 Lifetime Achievement Award van de Amerikaanse Glass Art Society, the spirit of his vision is continued by his former students as 'Vrij Glas'
Falkenberg etsmerk Chris Agterberg (1883 - 1948)

Ceramic designer who placed his designs with a variety of factories, 1925 -28 but very little was produced at Leerdam. The basic forms were painted in enamel, typical art deco borders were sometimes accompanied by a painted design of goldfish and reed or flowers in orange and black.
His monaogram is placed on the objects using paint.
Falkenberg etsmerk C.C.van Asch - van Wijck (1900 - 1932)

This mark appears on a single sculptural item from 1929. a female head (amd hand) with eyes closed which was produced in pressed glass. The artist was Cornelie van Asch-van Wijck (1900-1932)
Vermeire etsmerk Jules S. Vermeire (1885 - 1977)

Graduate of the Royal Academy in Ghent , Vermeire had worked as a sculptor in wood and stone before he turned his thoughts to glass.
In 1933 the factory produced two of his designs with matt-satin finish, joining the existing collection of work by other designers in this style (after Lalique). One is a female face with a flat back and accompanying purple stand and the other a stylish art-deco bird (eagle?) with a flat base which would have made a fine car-mascot.
Lensvelt etsmerk Frits Lensvelt (1886 - 1945)

Trained as graphic designer, painter and interior designer, Lensvelt was asked to design a number of designs for lamps, often using one or more suspended saucers under the lamp to reflect light onto the decorative cover above.
There are a number of other designers of Leerdam-made products not yet named on this page, some who only provided only a single design, and a few of international significance.
In recent years the crystal gallery and workshops in Leerdam have hosted many students and visitors from abroad as well as guest artists who demonstrate and/or exhibit, and who are not included here. This page is a continuing 'work in progress'! Please help us to correct any errors and add information wherever it is missing.