The Berlin Iron Manufactories

The Berlin iron manufactories are the most important German-language mourning and memorial jewellery industry of the nineteenth century. Where English mourning jewellery is identified with Whitby jet and French with black enamel and gold and French jet, German - more precisely, Prussian - mourning jewellery is identified with Berlin iron. The close iconographic and historical entanglement of the Wars of Liberation, the veneration of Queen Louise and the Biedermeier practice of mourning and remembrance makes Berlin iron a unique field in the history of jewellery.

Origin: the Prussian iron foundry system

The Prussian royal iron foundries arose in the late eighteenth and early nineteenth centuries as part of Prussia's state industrialisation strategy. Three main sites:

Gleiwitz (Upper Silesia) - founded in 1796 under Frederick William II. Main purpose: large military castings (cannon, shells, ammunition components) and industrial iron requirements. Jewellery casting develops from around 1804 as a secondary production.

Berlin - the royal iron foundry at the Invalidenpark in what is today the Mitte district, founded in 1804 under Frederick William III. The architect Karl Friedrich Schinkel (later court architect) designed many of the jewellery models in the 1810s and 1820s. The Berlin site became the style-setting centre of the entire art-casting tradition.

Sayn (Rhineland) - a foundry from 1815, following the Congress of Vienna, which transferred the Rhineland to Prussia. Specialising in especially fine filigree casting; the Sayn pieces are regarded among collectors as technically the most demanding.

To these are added smaller Prussian iron foundries (Lauchhammer, Wasseralfingen, Mägdesprung) and non-Prussian workshops in Saxony (the Lauchhammer iron foundry from 1725) and Bohemia (various smaller manufactories), which copied the Berlin iron model in part.

The Wars of Liberation and Queen Louise

The key political moment for Berlin iron is the appeal of 31 March 1813. The Prussian government - four years after the humiliating Peace of Tilsit and shortly before the resumption of war against Napoleon - called on the population to donate precious-metal jewellery to finance the war. In exchange the donors received jewellery of finely cast blackened iron bearing the inscription Gold gab ich für Eisen.

The gesture is culturally remarkable. It combines three layers of meaning:

1. Patriotic sacrifice. The donor gives personal wealth for the national cause. The iron jewellery received documents the sacrifice publicly.
2. Mourning and remembrance. The gesture falls in the period after the death of the popular Queen Louise of Prussia (1810). Queen Louise had herself supported the Prussian iron foundry industry in her short reign; the iron jewellery takes up a remembrance of the dead queen, venerated as a national figure of mourning.
3. Social visibility. The black iron jewellery signals the donor's social standing (she could sacrifice gold) and her patriotic conviction at the same time.

The campaign was a success. By the end of the Wars of Liberation in 1815 several tens of thousands of pieces of iron jewellery had been issued. The Prussian iron foundries - above all those in Berlin - produced at full capacity in the years 1813 to 1815.

Stylistic development

The oldest Berlin iron pieces (1804–1813) show heavy neoclassical forms - cameos with classical references, profile reliefs of Frederick the Great, heavy borders with acanthus ornament. Schinkel's designs from the 1810s onwards bring an important stylistic refinement: Gothic tracery, Romantic oak-leaf ornament, antique-revival vase and genius figures. Three phases of style can be distinguished:

Early phase (1804–1815) - neoclassical, often with political and patriotic reference. Heavy pieces, frequently with bands of inscription. The symbolism of the Wars of Liberation dominates.

Peak phase (1815–1840) - refined in the Biedermeier manner. Filigree Gothic-Romantic ornament, the finest tracery rosettes, small genius figures. The iconographic function shifts from the political to the private and sentimental.

Late phase (1840–1870) - historicist. A mixture of Gothic, neo-Romanesque, Renaissance and Rococo quotations. A broadening of style, but technical stagnation. The pieces become more conventional and lose their earlier originality.

Product range

The Berlin iron manufactories made a broad spectrum of jewellery:

• Mourning brooch in all sizes, often with Gothic tracery rosettes or antique-revival reliefs
• Necklace as a multi-link iron chain with a central pendant; characteristic are cannetille chain sections with especially fine filigree passages
• Bracelet as a chain of iron plaques with a gold-mounted clasp
• Pendant as single pieces on a gold chain
• Ring with a cast iron bezel
• Cameos - profile reliefs in an iron setting
• Tiaras and large head bands - as pieces of courtly display
• Buttons and small fittings - for the wardrobe of the upper middle classes
• Memorabilia - small iron plaques with a date of death, often as memorial pieces for the dead

Characteristic is the combination with gold. Pieces of pure iron jewellery are rare; the pieces mostly combine principal iron elements with gold or vermeil settings, clasps, borders or contrasting accents. This combination of materials distinguishes Berlin iron from purely matt black Whitby jet - the Prussian piece is never entirely black.

Technical particularities

The Berlin iron technique rests on a combination of several specialised steps:

1. Modelling. A wax model of the piece, often by an in-house modeller (in Berlin from the 1810s frequently Karl Friedrich Schinkel or his associates).
2. Making the mould. A very fine sand or clay casting mould, applied in several layers. The mould must take up the fine wax detail exactly.
3. Lost-wax casting. The wax is melted out and the molten iron poured into the resulting hollow mould. The casting temperature (around 1,250 to 1,450 °C) and the speed of pouring must be precisely controlled if the fine detail is to be captured.
4. Removal from the mould. The cast pieces are carefully released from the sand mould.
5. Cleaning up. Casting flash and sprue points are removed with fine files.
6. Blackening. The piece is heated and treated with linseed oil; this produces a matt black, corrosion-resistant surface layer (chemically an iron oxide / iron oleate complex).
7. Mounting. Gold settings, clasps and borders are added.

Steps 1 to 4 were carried out in the large works (Gleiwitz, Berlin); steps 5 to 7 often in specialised finishing and mounting workshops in Berlin itself.

Artistic collaboration

The Berlin iron tradition benefits from an unusually close connection between industry and artists of the first rank:

• Karl Friedrich Schinkel (1781–1841) - the most important Prussian architect designed numerous Berlin iron models in the 1810s and 1820s. His Gothic tracery rosettes and antique-revival genius figures shaped the aesthetic of the peak phase.
• Christian Daniel Rauch (1777–1857) - sculptor; designed reliefs and profile heads for the Berlin manufactory.
• Johann Conrad Geiss (1771–1846) - iron founder and workshop director; the leading technical figure of the Berlin manufactory.
• Werner Bartels, Eduard Lutter, Wilhelm Kratz - important modellers and workshop masters.

The close collaboration of leading artists distinguishes the Berlin iron tradition from the Whitby jet industry, which remained largely without recognised artistic involvement. Iron jewellery from Berlin carries - even in its more popular variants - an artistic connotation that secures it premium status in the collector market to this day.

Distribution and reception

In the Biedermeier period Berlin iron was worn not only in Prussia but throughout Germany, in Austria and also in the Netherlands, Scandinavia and Russia. In France and England it was catalogued as Fer de Berlin / Berlin iron jewellery and held in specialised collections. Queen Charlotte of Great Britain (wife of George III) was already wearing Berlin iron in the 1810s; the Russian imperial house was a customer too.

In the German-speaking world Berlin iron established itself as the typical middle-class line of mourning and memorial jewellery. The pieces are cheaper than gold and gemstones but more expensive than pure mass-produced ware; they suit the Biedermeier ideal of an "appropriate", unostentatious, culturally serious gesture of mourning.

Decline from 1870

From 1860 onwards the decline begins in several stages:

• Competition from Whitby jet and French jet. In the Victorian-inflected international mourning market, purely matt black materials prevail. Berlin iron, with its admixture of gold, appears too combined.
• Stylistic break. The historicist late phase loses the original stylistic originality. The pieces look conventional and are exchanged for lighter Victorian designs.
• Industrial restructuring. The Prussian royal iron foundries concentrate on architectural fittings, bridge components and large industrial castings. Jewellery becomes an unprofitable line.
• Political shift. With the founding of the German Empire in 1871 the specifically Prussian patriotic connotations lose their force; the commemorative reference to the Wars of Liberation and to Queen Louise becomes more abstract and more distant.

The royal iron foundry in Berlin was closed as an independent business in 1875. Gleiwitz went on producing into the early twentieth century, but practically without a jewellery line. Sayn was sold in 1873 and discontinued jewellery production.

Collecting and museums

The most important collections of Berlin iron are today at the Kunstgewerbemuseum Berlin (the most comprehensive collection, more than 1,000 pieces), the Deutsches Historisches Museum, the Schinkel Pavilion at Charlottenburg Palace (with Schinkel's original models) and in several regional museums in Silesia (today Poland) and along the Rhine.

Auction prices (as of the 2020s):

• Simple brooch or pendant: 400 to 1,500 €
• Elaborate pieces attributable to a Schinkel model: 2,000 to 8,000 €
• Complete parures (brooch, necklace, bracelet): 5,000 to 20,000 €
• Pieces with documented Gold gab ich für Eisen provenance: 3,000 to 15,000 €
• Pieces with court provenance: up to 50,000 €

The collector market is small but stable; demand has been growing since the 1990s, above all in Germany and the United States.

Berlin iron today

As a form of jewellery production the Berlin iron tradition is entirely extinct. There is no active workshop in the twenty-first century making the material in any appreciable quantity. A few specialised workshops (in Poland and in the Rhineland) carry out historicising individual commissions, mostly for museum restorations or particular collectors' orders.

In modern memorial jewellery Berlin iron plays no role. The historical significance of the manufactories lies, however, in their conceptual legacy: that an industrially produced, technically complex but materially "simple" material (cast iron instead of gold) can become a form of mourning and remembrance. This logic - meaning of the material instead of value of the material - is a Biedermeier and Prussian achievement that remains without direct parallel in the history of mourning jewellery.