Coatings with liquid metal,
the painted metal skin.
The refinement of different surfaces with precious metals such as gold, silver, bronze etc. has its roots in the long tradition of church restoration. The masters of sacred art recognized early on the importance of the refinement for the visible sublimity of church rooms.
Modern painting processes such as our coating with liquid metals are based on this art-historically diversified foundation. Various metal surfaces are possible: copper, bronze, tin bronze, steel, corten steel, brass, silver, gold and stainless steel and many more. In addition, the precious metal surfaces can be provided with structures, patina or different shine variants.
The origin of liquid metal coating lies in mythology
It was Midas from ancient mythology who is in some ways considered the spiritual father of surface refinement. The legendary king from Phrygia wanted everything he touched to turn to gold. But his greed for the precious metal almost cost him his life: everything became gold - even food and drink.
Midas threatened to die of thirst and starvation. On divine advice, King Midas bathed in the ancient river Paktolos. The gift of turning everything into gold was transferred to the river. Thus, this river became the most gold-rich river in Asia Minor and the ancient king gave his name to refined surfaces.
RGO liquid metal coatings - an eye-catching form of surface finishing
Today, the principle of finishing can be found in very different branches of industry: in the textile and printing industry, fashion and design, in the automotive industry or agricultural engineering. Even food, stones and even digital data sets are refined and thus individually enhanced.
The name RGO (Relief Granulate Surfaces) stands for the refinement of different surfaces. The metallic look and feel, the completely jointless coating and the excellent adhesive properties are a very special form of surface refinement. Liquid metal coating is also an excellent Alternative to PVD coating.
Liquid metal coatings for architecture, room and interior design
In the RGO process only metallic coatings are used: copper, bronze, brass, aluminium, iron, stainless steel and various mixed alloys are applied in several layers - depending on the nature and requirements of the respective substrate.
Plastics, wood, iron and composite panels are suitable for the coating. Also mineral surfaces such as granite and marble, terracotta and coloured sandstone, concrete, plaster and plaster, but also fibreglass are excellently suitable carrier materials for relief granulate surfaces.
Our real metal surfaces can be used seamlessly for a wide variety of shapes and elements and are therefore suitable for architecture, but also for any kind of interior design and living space.
Especially in areas where lightweight construction is in demand, but a noble and high-quality appearance is still important or desired, our high-end surfaces are optimally applicable. Many of our real metal surfaces have already been installed in luxury yachts. Here are a few examples of elaborately manufactured stair railings with different metal surfaces.
Relief granulate surfaces (RGO) at a glance
- proprietary process technologies
- for all paintable substrates
- individual interface design
- seamless and flawless real metal skin
- natural look and feel
- electronic shielding

If you have questions about our real metal coatings, real metal surfaces or liquid metal coatings, please call us. We will be pleased to help you. +49 8502 9173-0
Liquid metal surfaces - detailed and precise
Refined surfaces look very similar to the original.
A common example from practice: a bare iron door is attached to a wooden door frame for structural reasons. The customer's wish: the same appearance of the bare iron door and the wooden door frame. In addition, the wooden frame should "age", i.e. rust patina should develop on the frame - as on the iron door - over time.
The sophisticated process technology of liquid metal coating makes this possible! And much more: bronze surfaces become greenish and brownish like the original. Over time, aluminium applications become white-grey, copper coatings dark brown. And in the case of iron surfaces, a rusty patina is created.
The secret of the first-class nature and structure of the interfacial layer lies both in the professional coating process and in the corresponding pre-treatment. With this detailed procedure Lehner adapts, for example, refined workpieces to anodised window frames in a visually perfect way. A flawless real metal skin in high quality.

RGO surfaces are real metal surfaces - the basis without protective lacquer is real metal - depending on the specification, brass, bronze, copper etc... Surface irregularities, processing traces in the metal naturally deviate from homogeneous colour image phenomena depending on the type of treatment. Among other things, edge zones and boundary images can change colour in the continuous quantity due to the treatment at junctions and edges. Thus, patination also has a lively character. The surfaces are mostly processed by hand and their irregular gloss and appearance do not represent defects, but rather the metallizing character is given. In corners, edges and tapered junctions, grinding, patination and polishing deviations from the entire surface are visible.